Internet DRAFT - draft-ietf-bfd-yang
draft-ietf-bfd-yang
Network Working Group R. Rahman, Ed.
Internet-Draft Cisco Systems
Intended status: Standards Track L. Zheng, Ed.
Expires: February 2, 2019 Huawei Technologies
M. Jethanandani, Ed.
Xoriant Corporation
S. Pallagatti
Rtbrick
G. Mirsky
ZTE Corporation
August 1, 2018
YANG Data Model for Bidirectional Forwarding Detection (BFD)
draft-ietf-bfd-yang-17
Abstract
This document defines a YANG data model that can be used to configure
and manage Bidirectional Forwarding Detection (BFD).
The YANG modules in this document conform to the Network Management
Datastore Architecture (NMDA).
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 2, 2019.
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 4
2. Design of the Data Model . . . . . . . . . . . . . . . . . . 4
2.1. Design of Configuration Model . . . . . . . . . . . . . . 5
2.1.1. Common BFD configuration parameters . . . . . . . . . 6
2.1.2. Single-hop IP . . . . . . . . . . . . . . . . . . . . 7
2.1.3. Multihop IP . . . . . . . . . . . . . . . . . . . . . 7
2.1.4. MPLS Traffic Engineering Tunnels . . . . . . . . . . 8
2.1.5. MPLS Label Switched Paths . . . . . . . . . . . . . . 9
2.1.6. Link Aggregation Groups . . . . . . . . . . . . . . . 9
2.2. Design of Operational State Model . . . . . . . . . . . . 9
2.3. Notifications . . . . . . . . . . . . . . . . . . . . . . 10
2.4. RPC Operations . . . . . . . . . . . . . . . . . . . . . 10
2.5. BFD top level hierarchy . . . . . . . . . . . . . . . . . 10
2.6. BFD IP single-hop hierarchy . . . . . . . . . . . . . . . 10
2.7. BFD IP multihop hierarchy . . . . . . . . . . . . . . . . 12
2.8. BFD over LAG hierarchy . . . . . . . . . . . . . . . . . 14
2.9. BFD over MPLS LSPs hierarchy . . . . . . . . . . . . . . 18
2.10. BFD over MPLS-TE hierarchy . . . . . . . . . . . . . . . 20
2.11. Interaction with other YANG modules . . . . . . . . . . . 22
2.11.1. Module ietf-interfaces . . . . . . . . . . . . . . . 22
2.11.2. Module ietf-ip . . . . . . . . . . . . . . . . . . . 22
2.11.3. Module ietf-mpls . . . . . . . . . . . . . . . . . . 23
2.11.4. Module ietf-te . . . . . . . . . . . . . . . . . . . 23
2.12. IANA BFD YANG Module . . . . . . . . . . . . . . . . . . 23
2.13. BFD types YANG Module . . . . . . . . . . . . . . . . . . 26
2.14. BFD top-level YANG Module . . . . . . . . . . . . . . . . 39
2.15. BFD IP single-hop YANG Module . . . . . . . . . . . . . . 41
2.16. BFD IP multihop YANG Module . . . . . . . . . . . . . . . 44
2.17. BFD over LAG YANG Module . . . . . . . . . . . . . . . . 47
2.18. BFD over MPLS YANG Module . . . . . . . . . . . . . . . . 51
2.19. BFD over MPLS-TE YANG Module . . . . . . . . . . . . . . 55
3. Data Model examples . . . . . . . . . . . . . . . . . . . . . 58
3.1. IP single-hop . . . . . . . . . . . . . . . . . . . . . . 58
3.2. IP multihop . . . . . . . . . . . . . . . . . . . . . . . 59
3.3. LAG . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
3.4. MPLS . . . . . . . . . . . . . . . . . . . . . . . . . . 61
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4. Security Considerations . . . . . . . . . . . . . . . . . . . 62
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 66
5.1. IANA-Maintained iana-bfd-types module . . . . . . . . . . 70
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 70
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 70
7.1. Normative References . . . . . . . . . . . . . . . . . . 70
7.2. Informative References . . . . . . . . . . . . . . . . . 73
Appendix A. Echo function configuration example . . . . . . . . 73
A.1. Example YANG module for BFD echo function configuration . 74
Appendix B. Change log . . . . . . . . . . . . . . . . . . . . . 76
B.1. Changes between versions -16 and -17 . . . . . . . . . . 76
B.2. Changes between versions -15 and -16 . . . . . . . . . . 76
B.3. Changes between versions -14 and -15 . . . . . . . . . . 76
B.4. Changes between versions -13 and -14 . . . . . . . . . . 76
B.5. Changes between versions -12 and -13 . . . . . . . . . . 76
B.6. Changes between versions -11 and -12 . . . . . . . . . . 76
B.7. Changes between versions -10 and -11 . . . . . . . . . . 76
B.8. Changes between versions -09 and -10 . . . . . . . . . . 77
B.9. Changes between versions -08 and -09 . . . . . . . . . . 77
B.10. Changes between versions -07 and -08 . . . . . . . . . . 77
B.11. Changes between versions -06 and -07 . . . . . . . . . . 77
B.12. Changes between versions -05 and -06 . . . . . . . . . . 77
B.13. Changes between versions -04 and -05 . . . . . . . . . . 78
B.14. Changes between versions -03 and -04 . . . . . . . . . . 78
B.15. Changes between versions -02 and -03 . . . . . . . . . . 78
B.16. Changes between versions -01 and -02 . . . . . . . . . . 78
B.17. Changes between versions -00 and -01 . . . . . . . . . . 78
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 78
1. Introduction
This document defines a YANG data model that can be used to configure
and manage Bidirectional Forwarding Detection (BFD) [RFC5880]. BFD
is a network protocol which is used for liveness detection of
arbitrary paths between systems. Some examples of different types of
paths over which we have BFD:
1) Two systems directly connected via IP. This is known as BFD over
single-hop IP, a.k.a. BFD for IPv4 and IPv6 [RFC5881]
2) Two systems connected via multiple hops as described in BFD for
Multiple Hops. [RFC5883]
3) Two systems connected via MPLS Label Switched Paths (LSPs) as
described in BFD for MPLS LSP [RFC5884]
4) Two systems connected via a Link Aggregation Group (LAG) interface
as described in BFD on LAG Interfaces [RFC7130]
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5) Two systems connected via pseudowires (PWs), this is known as
Virtual Circuit Connectivity Verification (VCCV) as described in BFD
for PW VCCV [RFC5885]. This is not addressed in this document.
BFD typically does not operate on its own. Various control
protocols, also known as BFD clients, use the services provided by
BFD for their own operation as described in Generic Application of
BFD [RFC5882]. The obvious candidates which use BFD are those which
do not have "hellos" to detect failures, e.g. static routes, and
routing protocols whose "hellos" do not support sub-second failure
detection, e.g. OSPF and IS-IS.
The YANG modules in this document conform to the Network Management
Datastore Architecture (NMDA) [RFC8342]. This means that the data
models do not have separate top-level or sibling containers for
configuration and operational state data.
1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14 [RFC2119]
[RFC8174] when, and only when, they appear in all capitals, as shown
here.
1.2. Tree Diagrams
This document uses the graphical representation of data models
defined in [RFC8340].
2. Design of the Data Model
Since BFD is used for liveliness detection of various forwarding
paths, there is no uniform key to identify a BFD session, and so the
BFD data model is split in multiple YANG modules where each module
corresponds to one type of forwarding path. For example, BFD for IP
single-hop is in one YANG module and BFD for MPLS-TE is in another
YANG module. The main difference between these modules is how a BFD
session is uniquely identified, i.e the key for the list containing
the BFD sessions for that forwarding path. To avoid duplication of
BFD definitions, we have common types and groupings which are used by
all the modules.
A new control-plane protocol "bfdv1" is defined and a "bfd" container
is created under control-plane-protocol as specified in "A YANG Data
Model for Routing Management (NMDA Version)" [RFC8349]. This new
"bfd" container is augmented by all the YANG modules for their
respective specific information:
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1. ietf-bfd-ip-sh.yang augments "/routing/control-plane-protocols/
control-plane-protocol/bfd/" with the "ip-sh" container for BFD
sessions over IP single-hop.
2. ietf-bfd-ip-mh.yang augments "/routing/control-plane-protocols/
control-plane-protocol/bfd/" with the "ip-mh" container for BFD
sessions over IP multi-hop.
3. ietf-bfd-lag.yang augments "/routing/control-plane-protocols/
control-plane-protocol/bfd/" with the "lag" container for BFD
sessions over LAG.
4. ietf-bfd-mpls.yang augments "/routing/control-plane-protocols/
control-plane-protocol/bfd/" with the "mpls" container for BFD
over MPLS LSPs.
5. ietf-bfd-mpls-te.yang augments "/routing/control-plane-protocols/
control-plane-protocol/bfd/" with the "mpls-te" container for BFD
over MPLS-TE.
BFD can operate in the following contexts:
1. At the network device level
2. In Logical Network Elements as described in YANG Logical Network
Element [I-D.ietf-rtgwg-lne-model]
3. In Network Instances as described in YANG Logical Network Element
[I-D.ietf-rtgwg-ni-model]
When used at the network device level, the BFD YANG model is used
"as-is". When the BFD YANG model is used in a Logical Network
Element or in a Network Instance, then the BFD YANG model augments
the mounted routing model for the Logical Network Element or the
Network Instance.
2.1. Design of Configuration Model
The configuration model consists mainly of the parameters specified
in BFD [RFC5880]. Some examples are desired minimum transmit
interval, required minimum receive interval, detection multiplier,
etc
BFD clients are applications that use BFD for fast detection of
failures. Some implementations have BFD session configuration under
the BFD clients. For example, BFD session configuration under
routing applications such as OSPF, IS-IS, BGP etc. Other
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implementations have BFD session configuration centralized under BFD,
i.e. outside the multiple BFD clients.
The BFD parameters of interest to a BFD client are mainly the
multiplier and interval(s) since those parameters impact the
convergence time of the BFD clients when a failure occurs. Other
parameters such as BFD authentication are not specific to the
requirements of the BFD client. Ideally all configuration should be
centralized under BFD. However, this is a problem for clients of BFD
which auto-discover their peers. For example, IGPs do not have the
peer address configured, instead the IGP is enabled on an interface
and the IGP peers are auto-discovered. So for an operator to
configure BFD to an IGP peer, the operator would first have to
determine the peer addresses. And when a new peer is discovered, BFD
configuration would need to be added. To avoid this issue, we define
grouping client-cfg-parms in Section 2.13 for BFD clients to
configure BFD: this allows BFD clients such as the IGPs to have
configuration (multiplier and intervals) for the BFD sessions they
need. For example, when a new IGP peer is discovered, the IGP would
create a BFD session to the newly discovered peer and similarly when
an IGP peer goes away, the IGP would remove the BFD session to that
peer. The mechanism how the BFD sessions are created and removed by
the BFD clients is outside the scope of this document, but typically
this would be done by use of an API implemented by the BFD module on
the system. For BFD clients which create BFD sessions via their own
configuration, authentication parameters (if required) are still
specified in BFD.
2.1.1. Common BFD configuration parameters
The basic BFD configuration parameters are:
local-multiplier
This is the detection time multiplier as defined in BFD
[RFC5880].
desired-min-tx-interval
This is the Desired Min TX Interval as defined in BFD
[RFC5880].
required-min-rx-interval
This is the Required Min RX Interval as defined in BFD
[RFC5880].
Although BFD [RFC5880] allows for different values for transmit and
receive intervals, some implementations allow users to specify just
one interval which is used for both transmit and receive intervals or
separate values for transmit and receive intervals. The BFD YANG
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model supports this: there is a choice between "min-interval", used
for both transmit and receive intervals, and "desired-min-tx-
interval" and "required-min-rx-interval". This is supported via a
grouping which is used by the YANG modules for the various forwarding
paths.
For BFD authentication we have:
key-chain
This is a reference to key-chain defined in YANG Data Model
for Key Chains [RFC8177]. The keys, cryptographic
algorithms, key lifetime etc are all defined in the key-chain
model.
meticulous
This enables meticulous mode as per BFD [RFC5880].
2.1.2. Single-hop IP
For single-hop IP, there is an augment of the "bfd" data node in
Section 2. The "ip-sh" node contains a list of IP single-hop
sessions where each session is uniquely identified by the interface
and destination address pair. For the configuration parameters we
use what is defined in Section 2.1.1. The "ip-sh" node also contains
a list of interfaces, this is used to specify authentication
parameters for BFD sessions which are created by BFD clients, see
Section 2.1.
[RFC5880] and [RFC5881] do not specify whether echo function is
continuous or on demand. Therefore the mechanism used to start and
stop echo function is implementation specific and should be done by
augmentation:
1) Configuration. This is suitable for continuous echo function.
An example is provided in Appendix A.
2) RPC. This is suitable for on-demand echo function.
2.1.3. Multihop IP
For multihop IP, there is an augment of the "bfd" data node in
Section 2.
Because of multiple paths, there could be multiple multihop IP
sessions between a source and a destination address. We identify
this as a "session-group". The key for each "session-group" consists
of:
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source address
Address belonging to the local system as per BFD for Multiple
Hops [RFC5883]
destination address
Address belonging to the remote system as per BFD for
Multiple Hops [RFC5883]
For the configuration parameters we use what is defined in
Section 2.1.1
Here are some extra parameters:
tx-ttl
TTL of outgoing BFD control packets.
rx-ttl
Minimum TTL of incoming BFD control packets.
2.1.4. MPLS Traffic Engineering Tunnels
For MPLS-TE tunnels, BFD is configured under the MPLS-TE tunnel since
the desired failure detection parameters are a property of the MPLS-
TE tunnel. This is achieved by augmenting the MPLS-TE data model in
YANG Data Model for TE Topologies [I-D.ietf-teas-yang-te]. For BFD
parameters which are specific to the TE application, e.g. whether to
tear down the tunnel in the event of a BFD session failure, these
parameters will be defined in the YANG model of the MPLS-TE
application.
On top of the usual BFD parameters, we have the following per MPLS-TE
tunnel:
encap
Encapsulation for the BFD packets: choice between IP, G-ACh
and IP with G-ACh as per MPLS Generic Associated Channel
[RFC5586]
For general MPLS-TE data, "mpls-te" data node is added under the
"bfd" node in Section 2. Since some MPLS-TE tunnels are uni-
directional there is no MPLS-TE configuration for these tunnels on
the egress node (note that this does not apply to bi-directional
MPLS-TP tunnels). The BFD parameters for the egress node are added
under "mpls-te".
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2.1.5. MPLS Label Switched Paths
Here we address MPLS LSPs whose FEC is an IP address. The "bfd" node
in Section 2 is augmented with "mpls" which contains a list of
sessions uniquely identified by an IP prefix. Because of multiple
paths, there could be multiple MPLS sessions to an MPLS FEC. We
identify this as a "session-group".
Since these LSPs are uni-directional there is no LSP configuration on
the egress node.
The BFD parameters for the egress node are added under "mpls".
2.1.6. Link Aggregation Groups
Per BFD on LAG Interfaces [RFC7130], configuring BFD on LAG consists
of having micro-BFD sessions on each LAG member link. Since the BFD
parameters are an attribute of the LAG, they should be under the LAG.
However there is no LAG YANG model which we can augment. So a "lag"
data node is added to the "bfd" node in Section 2, the configuration
is per-LAG: we have a list of LAGs. The destination IP address of
the micro-BFD sessions is configured per-LAG and per address-family
(IPv4 and IPv6)
2.2. Design of Operational State Model
The operational state model contains both the overall statistics of
BFD sessions running on the device and the per session operational
information.
The overall statistics of BFD sessions consist of number of BFD
sessions, number of BFD sessions up etc. This information is
available globally (i.e. for all BFD sessions) under the "bfd" node
in Section 2 and also per type of forwarding path.
For each BFD session, mainly three categories of operational state
data are shown. The fundamental information of a BFD session such as
the local discriminator, remote discriminator and the capability of
supporting demand detect mode are shown in the first category. The
second category includes a BFD session running information, e.g. the
remote BFD state and the diagnostic code received. Another example
is the actual transmit interval between the control packets, which
may be different from the desired minimum transmit interval
configured, is shown in this category. Similar examples are actual
received interval between the control packets and the actual transmit
interval between the echo packets. The third category contains the
detailed statistics of the session, e.g. when the session
transitioned up/down and how long it has been in that state.
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For some path types, there may be more than 1 session on the virtual
path to the destination. For example, with IP multihop and MPLS
LSPs, there could be multiple BFD sessions from the source to the
same destination to test the various paths (ECMP) to the destination.
This is represented by having multiple "sessions" under each
"session-group".
2.3. Notifications
This YANG model defines notifications to inform end-users of
important events detected during the protocol operation. Pair of
local and remote discriminator identifies a BFD session on local
system. Notifications also give more important details about BFD
sessions; e.g. new state, time in previous state, network-instance
and the reason that the BFD session state changed. The notifications
are defined for each type of forwarding path but use groupings for
common information.
2.4. RPC Operations
None.
2.5. BFD top level hierarchy
At the "bfd" node under control-plane-protocol, there is no
configuration data, only operational state data. The operational
state data consist of overall BFD session statistics, i.e. for BFD on
all types of forwarding paths.
module: ietf-bfd
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol:
+--rw bfd
+--ro summary
+--ro number-of-sessions? yang:gauge32
+--ro number-of-sessions-up? yang:gauge32
+--ro number-of-sessions-down? yang:gauge32
+--ro number-of-sessions-admin-down? yang:gauge32
2.6. BFD IP single-hop hierarchy
An "ip-sh" node is added under "bfd" node in control-plane-protocol.
The configuration and operational state data for each BFD IP single-
hop session is under this "ip-sh" node.
module: ietf-bfd-ip-sh
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augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/bfd:bfd:
+--rw ip-sh
+--ro summary
| +--ro number-of-sessions? yang:gauge32
| +--ro number-of-sessions-up? yang:gauge32
| +--ro number-of-sessions-down? yang:gauge32
| +--ro number-of-sessions-admin-down? yang:gauge32
+--rw sessions
| +--rw session* [interface dest-addr]
| +--rw interface if:interface-ref
| +--rw dest-addr inet:ip-address
| +--rw source-addr? inet:ip-address
| +--rw local-multiplier? multiplier
| +--rw (interval-config-type)?
| | +--:(tx-rx-intervals)
| | | +--rw desired-min-tx-interval? uint32
| | | +--rw required-min-rx-interval? uint32
| | +--:(single-interval) {single-minimum-interval}?
| | +--rw min-interval? uint32
| +--rw demand-enabled? boolean
| | {demand-mode}?
| +--rw admin-down? boolean
| +--rw authentication! {authentication}?
| | +--rw key-chain? kc:key-chain-ref
| | +--rw meticulous? boolean
| +--ro path-type? identityref
| +--ro ip-encapsulation? boolean
| +--ro local-discriminator? discriminator
| +--ro remote-discriminator? discriminator
| +--ro remote-multiplier? multiplier
| +--ro demand-capability? boolean
| | {demand-mode}?
| +--ro source-port? inet:port-number
| +--ro dest-port? inet:port-number
| +--ro session-running
| | +--ro session-index? uint32
| | +--ro local-state? state
| | +--ro remote-state? state
| | +--ro local-diagnostic?
| | | iana-bfd-types:diagnostic
| | +--ro remote-diagnostic?
| | | iana-bfd-types:diagnostic
| | +--ro remote-authenticated? boolean
| | +--ro remote-authentication-type?
| | | iana-bfd-types:auth-type {authentication}?
| | +--ro detection-mode? enumeration
| | +--ro negotiated-tx-interval? uint32
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| | +--ro negotiated-rx-interval? uint32
| | +--ro detection-time? uint32
| | +--ro echo-tx-interval-in-use? uint32
| | {echo-mode}?
| +--ro session-statistics
| +--ro create-time?
| | yang:date-and-time
| +--ro last-down-time?
| | yang:date-and-time
| +--ro last-up-time?
| | yang:date-and-time
| +--ro down-count? yang:counter32
| +--ro admin-down-count? yang:counter32
| +--ro receive-packet-count? yang:counter64
| +--ro send-packet-count? yang:counter64
| +--ro receive-invalid-packet-count? yang:counter64
| +--ro send-failed-packet-count? yang:counter64
+--rw interfaces* [interface]
+--rw interface if:interface-ref
+--rw authentication! {authentication}?
+--rw key-chain? kc:key-chain-ref
+--rw meticulous? boolean
notifications:
+---n singlehop-notification
+--ro local-discr? discriminator
+--ro remote-discr? discriminator
+--ro new-state? state
+--ro state-change-reason? iana-bfd-types:diagnostic
+--ro time-of-last-state-change? yang:date-and-time
+--ro dest-addr? inet:ip-address
+--ro source-addr? inet:ip-address
+--ro session-index? uint32
+--ro path-type? identityref
+--ro interface? if:interface-ref
+--ro echo-enabled? boolean
2.7. BFD IP multihop hierarchy
An "ip-mh" node is added under the "bfd" node in cntrol-plane-
protocol. The configuration and operational state data for each BFD
IP multihop session is under this "ip-mh" node. In the operational
state model we support multiple BFD multihop sessions per remote
address (ECMP), the local discriminator is used as key.
module: ietf-bfd-ip-mh
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augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/bfd:bfd:
+--rw ip-mh
+--ro summary
| +--ro number-of-sessions? yang:gauge32
| +--ro number-of-sessions-up? yang:gauge32
| +--ro number-of-sessions-down? yang:gauge32
| +--ro number-of-sessions-admin-down? yang:gauge32
+--rw session-groups
+--rw session-group* [source-addr dest-addr]
+--rw source-addr inet:ip-address
+--rw dest-addr inet:ip-address
+--rw local-multiplier? multiplier
+--rw (interval-config-type)?
| +--:(tx-rx-intervals)
| | +--rw desired-min-tx-interval? uint32
| | +--rw required-min-rx-interval? uint32
| +--:(single-interval) {single-minimum-interval}?
| +--rw min-interval? uint32
+--rw demand-enabled? boolean
| {demand-mode}?
+--rw admin-down? boolean
+--rw authentication! {authentication}?
| +--rw key-chain? kc:key-chain-ref
| +--rw meticulous? boolean
+--rw tx-ttl? bfd-types:hops
+--rw rx-ttl bfd-types:hops
+--ro sessions* []
+--ro path-type? identityref
+--ro ip-encapsulation? boolean
+--ro local-discriminator? discriminator
+--ro remote-discriminator? discriminator
+--ro remote-multiplier? multiplier
+--ro demand-capability? boolean {demand-mode}?
+--ro source-port? inet:port-number
+--ro dest-port? inet:port-number
+--ro session-running
| +--ro session-index? uint32
| +--ro local-state? state
| +--ro remote-state? state
| +--ro local-diagnostic?
| | iana-bfd-types:diagnostic
| +--ro remote-diagnostic?
| | iana-bfd-types:diagnostic
| +--ro remote-authenticated? boolean
| +--ro remote-authentication-type?
| | iana-bfd-types:auth-type {authentication}?
| +--ro detection-mode? enumeration
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| +--ro negotiated-tx-interval? uint32
| +--ro negotiated-rx-interval? uint32
| +--ro detection-time? uint32
| +--ro echo-tx-interval-in-use? uint32
| {echo-mode}?
+--ro session-statistics
+--ro create-time?
| yang:date-and-time
+--ro last-down-time?
| yang:date-and-time
+--ro last-up-time?
| yang:date-and-time
+--ro down-count?
| yang:counter32
+--ro admin-down-count?
| yang:counter32
+--ro receive-packet-count?
| yang:counter64
+--ro send-packet-count?
| yang:counter64
+--ro receive-invalid-packet-count?
| yang:counter64
+--ro send-failed-packet-count?
yang:counter64
notifications:
+---n multihop-notification
+--ro local-discr? discriminator
+--ro remote-discr? discriminator
+--ro new-state? state
+--ro state-change-reason? iana-bfd-types:diagnostic
+--ro time-of-last-state-change? yang:date-and-time
+--ro dest-addr? inet:ip-address
+--ro source-addr? inet:ip-address
+--ro session-index? uint32
+--ro path-type? identityref
2.8. BFD over LAG hierarchy
A "lag" node is added under the "bfd" node in control-plane-protocol.
The configuration and operational state data for each BFD LAG session
is under this "lag" node.
module: ietf-bfd-lag
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/bfd:bfd:
+--rw lag
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+--rw micro-bfd-ipv4-session-statistics
| +--ro summary
| +--ro number-of-sessions? yang:gauge32
| +--ro number-of-sessions-up? yang:gauge32
| +--ro number-of-sessions-down? yang:gauge32
| +--ro number-of-sessions-admin-down? yang:gauge32
+--rw micro-bfd-ipv6-session-statistics
| +--ro summary
| +--ro number-of-sessions? yang:gauge32
| +--ro number-of-sessions-up? yang:gauge32
| +--ro number-of-sessions-down? yang:gauge32
| +--ro number-of-sessions-admin-down? yang:gauge32
+--rw sessions
+--rw session* [lag-name]
+--rw lag-name if:interface-ref
+--rw ipv4-dest-addr?
| inet:ipv4-address
+--rw ipv6-dest-addr?
| inet:ipv6-address
+--rw local-multiplier? multiplier
+--rw (interval-config-type)?
| +--:(tx-rx-intervals)
| | +--rw desired-min-tx-interval? uint32
| | +--rw required-min-rx-interval? uint32
| +--:(single-interval) {single-minimum-interval}?
| +--rw min-interval? uint32
+--rw demand-enabled? boolean
| {demand-mode}?
+--rw admin-down? boolean
+--rw authentication! {authentication}?
| +--rw key-chain? kc:key-chain-ref
| +--rw meticulous? boolean
+--rw use-ipv4? boolean
+--rw use-ipv6? boolean
+--ro member-links* [member-link]
+--ro member-link if:interface-ref
+--ro micro-bfd-ipv4
| +--ro path-type? identityref
| +--ro ip-encapsulation? boolean
| +--ro local-discriminator? discriminator
| +--ro remote-discriminator? discriminator
| +--ro remote-multiplier? multiplier
| +--ro demand-capability? boolean
| | {demand-mode}?
| +--ro source-port? inet:port-number
| +--ro dest-port? inet:port-number
| +--ro session-running
| | +--ro session-index? uint32
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| | +--ro local-state? state
| | +--ro remote-state? state
| | +--ro local-diagnostic?
| | | iana-bfd-types:diagnostic
| | +--ro remote-diagnostic?
| | | iana-bfd-types:diagnostic
| | +--ro remote-authenticated? boolean
| | +--ro remote-authentication-type?
| | | iana-bfd-types:auth-type
| | | {authentication}?
| | +--ro detection-mode? enumeration
| | +--ro negotiated-tx-interval? uint32
| | +--ro negotiated-rx-interval? uint32
| | +--ro detection-time? uint32
| | +--ro echo-tx-interval-in-use? uint32
| | {echo-mode}?
| +--ro session-statistics
| +--ro create-time?
| | yang:date-and-time
| +--ro last-down-time?
| | yang:date-and-time
| +--ro last-up-time?
| | yang:date-and-time
| +--ro down-count?
| | yang:counter32
| +--ro admin-down-count?
| | yang:counter32
| +--ro receive-packet-count?
| | yang:counter64
| +--ro send-packet-count?
| | yang:counter64
| +--ro receive-invalid-packet-count?
| | yang:counter64
| +--ro send-failed-packet-count?
| yang:counter64
+--ro micro-bfd-ipv6
+--ro path-type? identityref
+--ro ip-encapsulation? boolean
+--ro local-discriminator? discriminator
+--ro remote-discriminator? discriminator
+--ro remote-multiplier? multiplier
+--ro demand-capability? boolean
| {demand-mode}?
+--ro source-port? inet:port-number
+--ro dest-port? inet:port-number
+--ro session-running
| +--ro session-index? uint32
| +--ro local-state? state
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| +--ro remote-state? state
| +--ro local-diagnostic?
| | iana-bfd-types:diagnostic
| +--ro remote-diagnostic?
| | iana-bfd-types:diagnostic
| +--ro remote-authenticated? boolean
| +--ro remote-authentication-type?
| | iana-bfd-types:auth-type
| | {authentication}?
| +--ro detection-mode? enumeration
| +--ro negotiated-tx-interval? uint32
| +--ro negotiated-rx-interval? uint32
| +--ro detection-time? uint32
| +--ro echo-tx-interval-in-use? uint32
| {echo-mode}?
+--ro session-statistics
+--ro create-time?
| yang:date-and-time
+--ro last-down-time?
| yang:date-and-time
+--ro last-up-time?
| yang:date-and-time
+--ro down-count?
| yang:counter32
+--ro admin-down-count?
| yang:counter32
+--ro receive-packet-count?
| yang:counter64
+--ro send-packet-count?
| yang:counter64
+--ro receive-invalid-packet-count?
| yang:counter64
+--ro send-failed-packet-count?
yang:counter64
notifications:
+---n lag-notification
+--ro local-discr? discriminator
+--ro remote-discr? discriminator
+--ro new-state? state
+--ro state-change-reason? iana-bfd-types:diagnostic
+--ro time-of-last-state-change? yang:date-and-time
+--ro dest-addr? inet:ip-address
+--ro source-addr? inet:ip-address
+--ro session-index? uint32
+--ro path-type? identityref
+--ro lag-name? if:interface-ref
+--ro member-link? if:interface-ref
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2.9. BFD over MPLS LSPs hierarchy
An "mpls" node is added under the "bfd" node in control-plane-
protocol. The configuration is per MPLS FEC under this "mpls" node.
In the operational state model we support multiple BFD sessions per
MPLS FEC (ECMP), the local discriminator is used as key. The "mpls"
node can be used in a network device (top-level), or mounted in an
LNE or in a network instance.
module: ietf-bfd-mpls
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/bfd:bfd:
+--rw mpls
+--ro summary
| +--ro number-of-sessions? yang:gauge32
| +--ro number-of-sessions-up? yang:gauge32
| +--ro number-of-sessions-down? yang:gauge32
| +--ro number-of-sessions-admin-down? yang:gauge32
+--rw egress
| +--rw enable? boolean
| +--rw local-multiplier? multiplier
| +--rw (interval-config-type)?
| | +--:(tx-rx-intervals)
| | | +--rw desired-min-tx-interval? uint32
| | | +--rw required-min-rx-interval? uint32
| | +--:(single-interval) {single-minimum-interval}?
| | +--rw min-interval? uint32
| +--rw authentication! {authentication}?
| +--rw key-chain? kc:key-chain-ref
| +--rw meticulous? boolean
+--rw session-groups
+--rw session-group* [mpls-fec]
+--rw mpls-fec inet:ip-prefix
+--rw local-multiplier? multiplier
+--rw (interval-config-type)?
| +--:(tx-rx-intervals)
| | +--rw desired-min-tx-interval? uint32
| | +--rw required-min-rx-interval? uint32
| +--:(single-interval) {single-minimum-interval}?
| +--rw min-interval? uint32
+--rw demand-enabled? boolean
| {demand-mode}?
+--rw admin-down? boolean
+--rw authentication! {authentication}?
| +--rw key-chain? kc:key-chain-ref
| +--rw meticulous? boolean
+--ro sessions* []
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+--ro path-type? identityref
+--ro ip-encapsulation? boolean
+--ro local-discriminator? discriminator
+--ro remote-discriminator? discriminator
+--ro remote-multiplier? multiplier
+--ro demand-capability? boolean {demand-mode}?
+--ro source-port? inet:port-number
+--ro dest-port? inet:port-number
+--ro session-running
| +--ro session-index? uint32
| +--ro local-state? state
| +--ro remote-state? state
| +--ro local-diagnostic?
| | iana-bfd-types:diagnostic
| +--ro remote-diagnostic?
| | iana-bfd-types:diagnostic
| +--ro remote-authenticated? boolean
| +--ro remote-authentication-type?
| | iana-bfd-types:auth-type {authentication}?
| +--ro detection-mode? enumeration
| +--ro negotiated-tx-interval? uint32
| +--ro negotiated-rx-interval? uint32
| +--ro detection-time? uint32
| +--ro echo-tx-interval-in-use? uint32
| {echo-mode}?
+--ro session-statistics
| +--ro create-time?
| | yang:date-and-time
| +--ro last-down-time?
| | yang:date-and-time
| +--ro last-up-time?
| | yang:date-and-time
| +--ro down-count?
| | yang:counter32
| +--ro admin-down-count?
| | yang:counter32
| +--ro receive-packet-count?
| | yang:counter64
| +--ro send-packet-count?
| | yang:counter64
| +--ro receive-invalid-packet-count?
| | yang:counter64
| +--ro send-failed-packet-count?
| yang:counter64
+--ro mpls-dest-address? inet:ip-address
notifications:
+---n mpls-notification
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+--ro local-discr? discriminator
+--ro remote-discr? discriminator
+--ro new-state? state
+--ro state-change-reason? iana-bfd-types:diagnostic
+--ro time-of-last-state-change? yang:date-and-time
+--ro dest-addr? inet:ip-address
+--ro source-addr? inet:ip-address
+--ro session-index? uint32
+--ro path-type? identityref
+--ro mpls-dest-address? inet:ip-address
2.10. BFD over MPLS-TE hierarchy
YANG Data Model for TE Topologies [I-D.ietf-teas-yang-te] is
augmented. BFD is configured per MPLS-TE tunnel, and BFD session
operational state data is provided per MPLS-TE LSP.
module: ietf-bfd-mpls-te
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/bfd:bfd:
+--rw mpls-te
+--rw egress
| +--rw enable? boolean
| +--rw local-multiplier? multiplier
| +--rw (interval-config-type)?
| | +--:(tx-rx-intervals)
| | | +--rw desired-min-tx-interval? uint32
| | | +--rw required-min-rx-interval? uint32
| | +--:(single-interval) {single-minimum-interval}?
| | +--rw min-interval? uint32
| +--rw authentication! {authentication}?
| +--rw key-chain? kc:key-chain-ref
| +--rw meticulous? boolean
+--ro summary
+--ro number-of-sessions? yang:gauge32
+--ro number-of-sessions-up? yang:gauge32
+--ro number-of-sessions-down? yang:gauge32
+--ro number-of-sessions-admin-down? yang:gauge32
augment /te:te/te:tunnels/te:tunnel:
+--rw local-multiplier? multiplier
+--rw (interval-config-type)?
| +--:(tx-rx-intervals)
| | +--rw desired-min-tx-interval? uint32
| | +--rw required-min-rx-interval? uint32
| +--:(single-interval) {single-minimum-interval}?
| +--rw min-interval? uint32
+--rw demand-enabled? boolean {demand-mode}?
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+--rw admin-down? boolean
+--rw authentication! {authentication}?
| +--rw key-chain? kc:key-chain-ref
| +--rw meticulous? boolean
+--rw encap? identityref
augment /te:te/te:lsps-state/te:lsp:
+--ro path-type? identityref
+--ro ip-encapsulation? boolean
+--ro local-discriminator? discriminator
+--ro remote-discriminator? discriminator
+--ro remote-multiplier? multiplier
+--ro demand-capability? boolean {demand-mode}?
+--ro source-port? inet:port-number
+--ro dest-port? inet:port-number
+--ro session-running
| +--ro session-index? uint32
| +--ro local-state? state
| +--ro remote-state? state
| +--ro local-diagnostic? iana-bfd-types:diagnostic
| +--ro remote-diagnostic? iana-bfd-types:diagnostic
| +--ro remote-authenticated? boolean
| +--ro remote-authentication-type? iana-bfd-types:auth-type
| | {authentication}?
| +--ro detection-mode? enumeration
| +--ro negotiated-tx-interval? uint32
| +--ro negotiated-rx-interval? uint32
| +--ro detection-time? uint32
| +--ro echo-tx-interval-in-use? uint32 {echo-mode}?
+--ro session-statistics
| +--ro create-time? yang:date-and-time
| +--ro last-down-time? yang:date-and-time
| +--ro last-up-time? yang:date-and-time
| +--ro down-count? yang:counter32
| +--ro admin-down-count? yang:counter32
| +--ro receive-packet-count? yang:counter64
| +--ro send-packet-count? yang:counter64
| +--ro receive-invalid-packet-count? yang:counter64
| +--ro send-failed-packet-count? yang:counter64
+--ro mpls-dest-address? inet:ip-address
notifications:
+---n mpls-te-notification
+--ro local-discr? discriminator
+--ro remote-discr? discriminator
+--ro new-state? state
+--ro state-change-reason? iana-bfd-types:diagnostic
+--ro time-of-last-state-change? yang:date-and-time
+--ro dest-addr? inet:ip-address
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+--ro source-addr? inet:ip-address
+--ro session-index? uint32
+--ro path-type? identityref
+--ro mpls-dest-address? inet:ip-address
+--ro tunnel-name? string
2.11. Interaction with other YANG modules
Generic YANG Data Model for Connectionless OAM protocols
[I-D.ietf-lime-yang-connectionless-oam] describes how the LIME
connectionless OAM model could be extended to support BFD.
Also, the operation of the BFD data model depends on configuration
parameters that are defined in other YANG modules.
2.11.1. Module ietf-interfaces
The following boolean configuration is defined in A YANG Data Model
for Interface Management [RFC8343]:
/if:interfaces/if:interface/if:enabled
If this configuration is set to "false", no BFD packets can
be transmitted or received on that interface.
2.11.2. Module ietf-ip
The following boolean configuration is defined in A YANG Data Model
for IP Management [RFC8344]:
/if:interfaces/if:interface/ip:ipv4/ip:enabled
If this configuration is set to "false", no BFD IPv4 packets
can be transmitted or received on that interface.
/if:interfaces/if:interface/ip:ipv4/ip:forwarding
If this configuration is set to "false", no BFD IPv4 packets
can be transmitted or received on that interface.
/if:interfaces/if:interface/ip:ipv6/ip:enabled
If this configuration is set to "false", no BFD IPv6 packets
can be transmitted or received on that interface.
/if:interfaces/if:interface/ip:ipv6/ip:forwarding
If this configuration is set to "false", no BFD IPv6 packets
can be transmitted or received on that interface.
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2.11.3. Module ietf-mpls
The following boolean configuration is defined in A YANG Data Model
for MPLS Base [I-D.ietf-mpls-base-yang]:
/rt:routing/mpls:mpls/mpls:interface/mpls:config/mpls:enabled
If this configuration is set to "false", no BFD MPLS packets
can be transmitted or received on that interface.
2.11.4. Module ietf-te
The following configuration is defined in the "ietf-te" YANG module
YANG Data Model for TE Topology [I-D.ietf-teas-yang-te]:
/ietf-te:te/ietf-te:tunnels/ietf-te:tunnel/ietf-te:config/ietf-
te:admin-status
If this configuration is not set to "state-up", no BFD MPLS
packets can be transmitted or received on that tunnel.
2.12. IANA BFD YANG Module
<CODE BEGINS> file "iana-bfd-types@2018-08-01.yang"
module iana-bfd-types {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:iana-bfd-types";
prefix "iana-bfd-types";
organization "IANA";
contact
" Internet Assigned Numbers Authority
Postal: ICANN
12025 Waterfront Drive, Suite 300
Los Angeles, CA 90094-2536
United States of America
Tel: +1 310 823 9358
<mailto:iana@iana.org>";
description
"This module defines YANG data types for IANA-registered
BFD parameters.
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This YANG module is maintained by IANA and reflects the
'BFD Diagnostic Codes' and 'BFD Authentication Types' registries.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove
// this note
reference "RFC XXXX";
revision 2018-08-01 {
description "Initial revision.";
reference "RFC XXXX: IANA BFD YANG Data Types.";
}
/*
* Type Definitions
*/
typedef diagnostic {
type enumeration {
enum none {
value 0;
description "None";
}
enum control-expiry {
value 1;
description "Control timer expiry";
}
enum echo-failed {
value 2;
description "Echo failure";
}
enum neighbor-down {
value 3;
description "Neighbor down";
}
enum forwarding-reset {
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value 4;
description "Forwarding reset";
}
enum path-down {
value 5;
description "Path down";
}
enum concatenated-path-down {
value 6;
description "Concatenated path down";
}
enum admin-down {
value 7;
description "Admin down";
}
enum reverse-concatenated-path-down {
value 8;
description "Reverse concatenated path down";
}
enum mis-connectivity-defect {
value 9;
description "Mis-connectivity defect as specified in RFC6428";
}
}
description
"BFD diagnostic as defined in RFC 5880, values are maintained in
the 'BFD Diagnostic Codes' IANA registry. Range is 0 to 31.";
}
typedef auth-type {
type enumeration {
enum reserved {
value 0;
description "Reserved";
}
enum simple-password {
value 1;
description "Simple password";
}
enum keyed-md5 {
value 2;
description "Keyed MD5";
}
enum meticulous-keyed-md5 {
value 3;
description "Meticulous keyed MD5";
}
enum keyed-sha1 {
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value 4;
description "Keyed SHA1";
}
enum meticulous-keyed-sha1 {
value 5;
description "Meticulous keyed SHA1";
}
}
description
"BFD authentication type as defined in RFC 5880, values are
maintained in the 'BFD Authentication Types' IANA registry.
Range is 0 to 255.";
}
}
<CODE ENDS>
2.13. BFD types YANG Module
This YANG module imports typedefs from [RFC6991], [RFC8177] and the
"control-plane-protocol" identity from [RFC8349].
<CODE BEGINS> file "ietf-bfd-types@2018-08-01.yang"
module ietf-bfd-types {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-bfd-types";
prefix "bfd-types";
// RFC Ed.: replace occurences of XXXX with actual RFC number and
// remove this note
import iana-bfd-types {
prefix "iana-bfd-types";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-inet-types {
prefix "inet";
reference "RFC 6991: Common YANG Data Types";
}
import ietf-yang-types {
prefix "yang";
reference "RFC 6991: Common YANG Data Types";
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}
import ietf-routing {
prefix "rt";
reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA version)";
}
import ietf-key-chain {
prefix "kc";
reference "RFC 8177: YANG Data Model for Key Chains";
}
organization "IETF BFD Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/bfd>
WG List: <rtg-bfd@ietf.org>
Editors: Reshad Rahman (rrahman@cisco.com),
Lianshu Zheng (vero.zheng@huawei.com),
Mahesh Jethanandani (mjethanandani@gmail.com)";
description
"This module contains a collection of BFD specific YANG data type
definitions, as per RFC 5880, and also groupings which are common
to other BFD YANG modules.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
reference "RFC XXXX";
revision 2018-08-01 {
description "Initial revision.";
reference "RFC XXXX: YANG Data Model for BFD";
}
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/*
* Feature definitions
*/
feature single-minimum-interval {
description
"This feature indicates that the server supports configuration
of one minimum interval value which is used for both transmit and
receive minimum intervals.";
}
feature authentication {
description
"This feature indicates that the server supports BFD
authentication.";
reference
"RFC 5880: Bidirectional Forwarding Detection (BFD),
section 6.7.";
}
feature demand-mode {
description
"This feature indicates that the server supports BFD demand
mode.";
reference
"RFC 5880: Bidirectional Forwarding Detection (BFD),
section 6.6.";
}
feature echo-mode {
description
"This feature indicates that the server supports BFD echo
mode.";
reference
"RFC 5880: Bidirectional Forwarding Detection (BFD),
section 6.4.";
}
/*
* Identity definitions
*/
identity bfdv1 {
base "rt:control-plane-protocol";
description "BFD protocol version 1.";
reference
"RFC 5880: Bidirectional Forwarding Detection (BFD).";
}
identity path-type {
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description
"Base identity for BFD path type. The path type indicates
the type of path on which BFD is running.";
}
identity path-ip-sh {
base path-type;
description "BFD on IP single hop.";
reference
"RFC 5881: Bidirectional Forwarding Detection (BFD)
for IPv4 and IPv6 (Single Hop).";
}
identity path-ip-mh {
base path-type;
description "BFD on IP multihop paths.";
reference
"RFC 5883: Bidirectional Forwarding Detection (BFD) for
Multihop Paths.";
}
identity path-mpls-te {
base path-type;
description
"BFD on MPLS Traffic Engineering.";
reference
"RFC 5884: Bidirectional Forwarding Detection (BFD)
for MPLS Label Switched Paths (LSPs).";
}
identity path-mpls-lsp {
base path-type;
description
"BFD on MPLS Label Switched Path.";
reference
"RFC 5884: Bidirectional Forwarding Detection (BFD)
for MPLS Label Switched Paths (LSPs).";
}
identity path-lag {
base path-type;
description
"Micro-BFD on LAG member links.";
reference
"RFC 7130: Bidirectional Forwarding Detection (BFD) on
Link Aggregation Group (LAG) Interfaces.";
}
identity encap-type {
description
"Base identity for BFD encapsulation type.";
}
identity encap-ip {
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base encap-type;
description "BFD with IP encapsulation.";
}
/*
* Type Definitions
*/
typedef discriminator {
type uint32;
description "BFD discriminator as described in RFC 5880.";
}
typedef state {
type enumeration {
enum adminDown {
value 0;
description "admindown";
}
enum down {
value 1;
description "down";
}
enum init {
value 2;
description "init";
}
enum up {
value 3;
description "up";
}
}
description "BFD state as defined in RFC 5880.";
}
typedef multiplier {
type uint8 {
range 1..255;
}
description "BFD multiplier as described in RFC 5880.";
}
typedef hops {
type uint8 {
range 1..255;
}
description
"This corresponds to Time To Live for IPv4 and corresponds to hop
limit for IPv6.";
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}
/*
* Groupings
*/
grouping auth-parms {
description
"Grouping for BFD authentication parameters
(see section 6.7 of RFC 5880).";
container authentication {
if-feature authentication;
presence
"Enables BFD authentication (see section 6.7 of RFC 5880).";
description "Parameters for BFD authentication.";
leaf key-chain {
type kc:key-chain-ref;
description "Name of the key-chain as per RFC 8177.";
}
leaf meticulous {
type boolean;
description
"Enables meticulous mode as described in section 6.7 " +
"of RFC 5880.";
}
}
}
grouping base-cfg-parms {
description "BFD grouping for base config parameters.";
leaf local-multiplier {
type multiplier;
default 3;
description "Multiplier transmitted by local system.";
}
choice interval-config-type {
description
"Two interval values or one value used for both transmit and
receive.";
case tx-rx-intervals {
leaf desired-min-tx-interval {
type uint32;
units microseconds;
default 1000000;
description
"Desired minimum transmit interval of control packets.";
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}
leaf required-min-rx-interval {
type uint32;
units microseconds;
default 1000000;
description
"Required minimum receive interval of control packets.";
}
}
case single-interval {
if-feature single-minimum-interval;
leaf min-interval {
type uint32;
units microseconds;
default 1000000;
description
"Desired minimum transmit interval and required " +
"minimum receive interval of control packets.";
}
}
}
}
grouping client-cfg-parms {
description
"BFD grouping for configuration parameters
used by clients of BFD, e.g. IGP or MPLS.";
leaf enable {
type boolean;
default false;
description
"Indicates whether the BFD is enabled.";
}
uses base-cfg-parms;
}
grouping common-cfg-parms {
description
"BFD grouping for common configuration parameters.";
uses base-cfg-parms;
leaf demand-enabled {
if-feature demand-mode;
type boolean;
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default false;
description
"To enable demand mode.";
}
leaf admin-down {
type boolean;
default false;
description
"Is the BFD session administratively down.";
}
uses auth-parms;
}
grouping all-session {
description "BFD session operational information";
leaf path-type {
type identityref {
base path-type;
}
config "false";
description
"BFD path type, this indicates the path type that BFD is
running on.";
}
leaf ip-encapsulation {
type boolean;
config "false";
description "Whether BFD encapsulation uses IP.";
}
leaf local-discriminator {
type discriminator;
config "false";
description "Local discriminator.";
}
leaf remote-discriminator {
type discriminator;
config "false";
description "Remote discriminator.";
}
leaf remote-multiplier {
type multiplier;
config "false";
description "Remote multiplier.";
}
leaf demand-capability {
if-feature demand-mode;
type boolean;
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config "false";
description "Local demand mode capability.";
}
leaf source-port {
when "../ip-encapsulation = 'true'" {
description
"Source port valid only when IP encapsulation is used.";
}
type inet:port-number;
config "false";
description "Source UDP port";
}
leaf dest-port {
when "../ip-encapsulation = 'true'" {
description
"Destination port valid only when IP encapsulation is used.";
}
type inet:port-number;
config "false";
description "Destination UDP port.";
}
container session-running {
config "false";
description "BFD session running information.";
leaf session-index {
type uint32;
description
"An index used to uniquely identify BFD sessions.";
}
leaf local-state {
type state;
description "Local state.";
}
leaf remote-state {
type state;
description "Remote state.";
}
leaf local-diagnostic {
type iana-bfd-types:diagnostic;
description "Local diagnostic.";
}
leaf remote-diagnostic {
type iana-bfd-types:diagnostic;
description "Remote diagnostic.";
}
leaf remote-authenticated {
type boolean;
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description
"Indicates whether incoming BFD control packets are
authenticated.";
}
leaf remote-authentication-type {
when "../remote-authenticated = 'true'" {
description
"Only valid when incoming BFD control packets are
authenticated.";
}
if-feature authentication;
type iana-bfd-types:auth-type;
description
"Authentication type of incoming BFD control packets.";
}
leaf detection-mode {
type enumeration {
enum async-with-echo {
value "1";
description "Async with echo.";
}
enum async-without-echo {
value "2";
description "Async without echo.";
}
enum demand-with-echo {
value "3";
description "Demand with echo.";
}
enum demand-without-echo {
value "4";
description "Demand without echo.";
}
}
description "Detection mode.";
}
leaf negotiated-tx-interval {
type uint32;
units microseconds;
description "Negotiated transmit interval.";
}
leaf negotiated-rx-interval {
type uint32;
units microseconds;
description "Negotiated receive interval.";
}
leaf detection-time {
type uint32;
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units microseconds;
description "Detection time.";
}
leaf echo-tx-interval-in-use {
when "../../path-type = 'bfd-types:path-ip-sh'" {
description
"Echo is supported for IP single-hop only.";
}
if-feature echo-mode;
type uint32;
units microseconds;
description "Echo transmit interval in use.";
}
}
container session-statistics {
config "false";
description "BFD per-session statistics.";
leaf create-time {
type yang:date-and-time;
description
"Time and date when this session was created.";
}
leaf last-down-time {
type yang:date-and-time;
description
"Time and date of last time this session went down.";
}
leaf last-up-time {
type yang:date-and-time;
description
"Time and date of last time this session went up.";
}
leaf down-count {
type yang:counter32;
description
"The number of times this session has transitioned in the
down state.";
}
leaf admin-down-count {
type yang:counter32;
description
"The number of times this session has transitioned in the
admin-down state.";
}
leaf receive-packet-count {
type yang:counter64;
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description
"Count of received packets in this session. This includes
valid and invalid received packets.";
}
leaf send-packet-count {
type yang:counter64;
description "Count of sent packets in this session.";
}
leaf receive-invalid-packet-count {
type yang:counter64;
description
"Count of invalid received packets in this session.";
}
leaf send-failed-packet-count {
type yang:counter64;
description
"Count of packets which failed to be sent in this session.";
}
}
}
grouping session-statistics-summary {
description "Grouping for session statistics summary.";
container summary {
config false;
description "BFD session statistics summary.";
leaf number-of-sessions {
type yang:gauge32;
description "Number of BFD sessions.";
}
leaf number-of-sessions-up {
type yang:gauge32;
description
"Number of BFD sessions currently in up state (as defined
in RFC 5880).";
}
leaf number-of-sessions-down {
type yang:gauge32;
description
"Number of BFD sessions currently in down or init state
but not admin-down (as defined in RFC 5880).";
}
leaf number-of-sessions-admin-down {
type yang:gauge32;
description
"Number of BFD sessions currently in admin-down state (as
defined in RFC 5880).";
}
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}
}
grouping notification-parms {
description
"This group describes common parameters that will be sent " +
"as part of BFD notification.";
leaf local-discr {
type discriminator;
description "BFD local discriminator.";
}
leaf remote-discr {
type discriminator;
description "BFD remote discriminator.";
}
leaf new-state {
type state;
description "Current BFD state.";
}
leaf state-change-reason {
type iana-bfd-types:diagnostic;
description "BFD state change reason.";
}
leaf time-of-last-state-change {
type yang:date-and-time;
description
"Calendar time of previous state change.";
}
leaf dest-addr {
type inet:ip-address;
description "BFD peer address.";
}
leaf source-addr {
type inet:ip-address;
description "BFD local address.";
}
leaf session-index {
type uint32;
description "An index used to uniquely identify BFD sessions.";
}
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leaf path-type {
type identityref {
base path-type;
}
description "BFD path type.";
}
}
}
<CODE ENDS>
2.14. BFD top-level YANG Module
This YANG module imports and augments "/routing/control-plane-
protocols/control-plane-protocol" from [RFC8349].
<CODE BEGINS> file "ietf-bfd@2018-08-01.yang"
module ietf-bfd {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-bfd";
prefix "bfd";
// RFC Ed.: replace occurences of XXXX with actual RFC number and
// remove this note
import ietf-bfd-types {
prefix "bfd-types";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-routing {
prefix "rt";
reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA version)";
}
organization "IETF BFD Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/bfd>
WG List: <rtg-bfd@ietf.org>
Editors: Reshad Rahman (rrahman@cisco.com),
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Lianshu Zheng (vero.zheng@huawei.com),
Mahesh Jethanandani (mjethanandani@gmail.com)";
description
"This module contains the YANG definition for BFD parameters as
per RFC 5880.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
reference "RFC XXXX";
revision 2018-08-01 {
description "Initial revision.";
reference "RFC XXXX: YANG Data Model for BFD";
}
augment "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol" {
when "derived-from-or-self(rt:type, 'bfd-types:bfdv1')" {
description
"This augmentation is only valid for a control-plane protocol
instance of BFD (type 'bfdv1').";
}
description "BFD augmentation.";
container bfd {
description "BFD top level container.";
uses bfd-types:session-statistics-summary;
}
}
}
<CODE ENDS>
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2.15. BFD IP single-hop YANG Module
This YANG module imports "interface-ref" from [RFC8343], typedefs
from [RFC6991] and augments "/routing/control-plane-protocols/
control-plane-protocol" from [RFC8349].
<CODE BEGINS> file "ietf-bfd-ip-sh@2018-08-01.yang"
module ietf-bfd-ip-sh {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-bfd-ip-sh";
prefix "bfd-ip-sh";
// RFC Ed.: replace occurences of XXXX with actual RFC number and
// remove this note
import ietf-bfd-types {
prefix "bfd-types";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-bfd {
prefix "bfd";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-interfaces {
prefix "if";
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-inet-types {
prefix "inet";
reference "RFC 6991: Common YANG Data Types";
}
import ietf-routing {
prefix "rt";
reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA version)";
}
organization "IETF BFD Working Group";
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contact
"WG Web: <http://tools.ietf.org/wg/bfd>
WG List: <rtg-bfd@ietf.org>
Editors: Reshad Rahman (rrahman@cisco.com),
Lianshu Zheng (vero.zheng@huawei.com),
Mahesh Jethanandani (mjethanandani@gmail.com)";
description
"This module contains the YANG definition for BFD IP single-hop
as per RFC 5881.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
reference "RFC XXXX";
revision 2018-08-01 {
description "Initial revision.";
reference "RFC XXXX: A YANG data model for BFD IP single-hop";
}
/*
* Augments
*/
augment "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/bfd:bfd" {
description "BFD augmentation for IP single-hop";
container ip-sh {
description "BFD IP single-hop top level container";
uses bfd-types:session-statistics-summary;
container sessions {
description
"BFD IP single-hop sessions.";
list session {
key "interface dest-addr";
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description "List of IP single-hop sessions.";
leaf interface {
type if:interface-ref;
description
"Interface on which the BFD session is running.";
}
leaf dest-addr {
type inet:ip-address;
description "IP address of the peer.";
}
leaf source-addr {
type inet:ip-address;
description "Local IP address.";
}
uses bfd-types:common-cfg-parms;
uses bfd-types:all-session;
}
}
list interfaces {
key "interface";
description "List of interfaces.";
leaf interface {
type if:interface-ref;
description
"BFD information for this interface.";
}
uses bfd-types:auth-parms;
}
}
}
/*
* Notifications
*/
notification singlehop-notification {
description
"Notification for BFD single-hop session state change. An " +
"implementation may rate-limit notifications, e.g. when a " +
"session is continuously changing state.";
uses bfd-types:notification-parms;
leaf interface {
type if:interface-ref;
description "Interface to which this BFD session belongs to.";
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}
leaf echo-enabled {
type boolean;
description "Was echo enabled for BFD.";
}
}
}
<CODE ENDS>
2.16. BFD IP multihop YANG Module
This YANG module imports typedefs from [RFC6991] and augments
"/routing/control-plane-protocols/control-plane-protocol" from
[RFC8349].
<CODE BEGINS> file "ietf-bfd-ip-mh@2018-08-01.yang"
module ietf-bfd-ip-mh {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-bfd-ip-mh";
prefix "bfd-ip-mh";
// RFC Ed.: replace occurences of XXXX with actual RFC number and
// remove this note
import ietf-bfd-types {
prefix "bfd-types";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-bfd {
prefix "bfd";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-inet-types {
prefix "inet";
reference "RFC 6991: Common YANG Data Types";
}
import ietf-routing {
prefix "rt";
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reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA version)";
}
organization "IETF BFD Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/bfd>
WG List: <rtg-bfd@ietf.org>
Editors: Reshad Rahman (rrahman@cisco.com),
Lianshu Zheng (vero.zheng@huawei.com),
Mahesh Jethanandani (mjethanandani@gmail.com)";
description
"This module contains the YANG definition for BFD IP multi-hop
as per RFC 5883.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
reference "RFC XXXX";
revision 2018-08-01 {
description "Initial revision.";
reference "RFC XXXX: A YANG data model for BFD IP multihop.";
}
/*
* Augments
*/
augment "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/bfd:bfd" {
description "BFD augmentation for IP multihop.";
container ip-mh {
description "BFD IP multihop top level container.";
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uses bfd-types:session-statistics-summary;
container session-groups {
description
"BFD IP multi-hop session groups.";
list session-group {
key "source-addr dest-addr";
description
"Group of BFD IP multi-hop sessions (for ECMP). A " +
"group of sessions is between 1 source and 1 " +
"destination, each session has a different field " +
"in UDP/IP hdr for ECMP.";
leaf source-addr {
type inet:ip-address;
description
"Local IP address.";
}
leaf dest-addr {
type inet:ip-address;
description
"IP address of the peer.";
}
uses bfd-types:common-cfg-parms;
leaf tx-ttl {
type bfd-types:hops;
default 255;
description "Hop count of outgoing BFD control packets.";
}
leaf rx-ttl {
type bfd-types:hops;
mandatory true;
description
"Minimum allowed hop count value for incoming BFD control
packets. Control packets whose hop count is lower than
this value are dropped.";
}
list sessions {
config false;
description
"The multiple BFD sessions between a source and a " +
"destination.";
uses bfd-types:all-session;
}
}
}
}
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}
/*
* Notifications
*/
notification multihop-notification {
description
"Notification for BFD multi-hop session state change. An " +
"implementation may rate-limit notifications, e.g. when a " +
"session is continuously changing state.";
uses bfd-types:notification-parms;
}
}
<CODE ENDS>
2.17. BFD over LAG YANG Module
This YANG module imports "interface-ref" from [RFC8343], typedefs
from [RFC6991] and augments "/routing/control-plane-protocols/
control-plane-protocol" from [RFC8349].
<CODE BEGINS> file "ietf-bfd-lag@2018-08-01.yang"
module ietf-bfd-lag {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-bfd-lag";
prefix "bfd-lag";
// RFC Ed.: replace occurences of XXXX with actual RFC number and
// remove this note
import ietf-bfd-types {
prefix "bfd-types";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-bfd {
prefix "bfd";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-interfaces {
prefix "if";
Rahman, et al. Expires February 2, 2019 [Page 47]
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reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-inet-types {
prefix "inet";
reference "RFC 6991: Common YANG Data Types";
}
import ietf-routing {
prefix "rt";
reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA version)";
}
organization "IETF BFD Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/bfd>
WG List: <rtg-bfd@ietf.org>
Editors: Reshad Rahman (rrahman@cisco.com),
Lianshu Zheng vero.zheng@huawei.com),
Mahesh Jethanandani (mjethanandani@gmail.com)";
description
"This module contains the YANG definition for BFD over LAG
interfaces as per RFC7130.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
reference "RFC XXXX";
revision 2018-08-01 {
description "Initial revision.";
reference "RFC XXXX: A YANG data model for BFD over LAG";
Rahman, et al. Expires February 2, 2019 [Page 48]
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}
/*
* Augments
*/
augment "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/bfd:bfd" {
description "BFD augmentation for LAG";
container lag {
description "BFD over LAG top level container";
container micro-bfd-ipv4-session-statistics {
description "Micro-BFD IPv4 session counters.";
uses bfd-types:session-statistics-summary;
}
container micro-bfd-ipv6-session-statistics {
description "Micro-BFD IPv6 session counters.";
uses bfd-types:session-statistics-summary;
}
container sessions {
description
"BFD over LAG sessions";
list session {
key "lag-name";
description "List of BFD over LAG sessions.";
leaf lag-name {
type if:interface-ref ;
description "Name of the LAG";
}
leaf ipv4-dest-addr {
type inet:ipv4-address;
description
"IPv4 address of the peer, for IPv4 micro-BFD.";
}
leaf ipv6-dest-addr {
type inet:ipv6-address;
description
"IPv6 address of the peer, for IPv6 micro-BFD.";
}
uses bfd-types:common-cfg-parms;
leaf use-ipv4 {
type boolean;
description "Using IPv4 micro-BFD.";
}
leaf use-ipv6 {
type boolean;
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description "Using IPv6 micro-BFD.";
}
list member-links {
key "member-link";
config false;
description
"Micro-BFD over LAG. This represents one member link.";
leaf member-link {
type if:interface-ref;
description
"Member link on which micro-BFD is running.";
}
container micro-bfd-ipv4 {
when "../../use-ipv4 = 'true'" {
description "Needed only if IPv4 is used.";
}
description
"Micro-BFD IPv4 session state on member link.";
uses bfd-types:all-session;
}
container micro-bfd-ipv6 {
when "../../use-ipv6 = 'true'" {
description "Needed only if IPv6 is used.";
}
description
"Micro-BFD IPv6 session state on member link.";
uses bfd-types:all-session;
}
}
}
}
}
}
/*
* Notifications
*/
notification lag-notification {
description
"Notification for BFD over LAG session state change. " +
"An implementation may rate-limit notifications, e.g. when a " +
"session is continuously changing state.";
uses bfd-types:notification-parms;
leaf lag-name {
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type if:interface-ref;
description "LAG interface name.";
}
leaf member-link {
type if:interface-ref;
description "Member link on which BFD is running.";
}
}
}
<CODE ENDS>
2.18. BFD over MPLS YANG Module
This YANG module imports typedefs from [RFC6991] and augments
"/routing/control-plane-protocols/control-plane-protocol" from
[RFC8349].
<CODE BEGINS> file "ietf-bfd-mpls@2018-08-01.yang"
module ietf-bfd-mpls {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-bfd-mpls";
prefix "bfd-mpls";
// RFC Ed.: replace occurences of XXXX with actual RFC number and
// remove this note
import ietf-bfd-types {
prefix "bfd-types";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-bfd {
prefix "bfd";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-inet-types {
prefix "inet";
reference "RFC 6991: Common YANG Data Types";
}
import ietf-routing {
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prefix "rt";
reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA version)";
}
organization "IETF BFD Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/bfd>
WG List: <rtg-bfd@ietf.org>
Editors: Reshad Rahman (rrahman@cisco.com),
Lianshu Zheng (vero.zheng@huawei.com),
Mahesh Jethanandani (mjethanandani@gmail.com)";
description
"This module contains the YANG definition for BFD parameters for
MPLS LSPs as per RFC 5884.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
reference "RFC XXXX";
revision 2018-08-01 {
description "Initial revision.";
reference "RFC XXXX: A YANG data model for BFD over MPLS LSPs";
}
/*
* Identity definitions
*/
identity encap-gach {
base bfd-types:encap-type;
description
"BFD with G-ACh encapsulation as per RFC 5586.";
}
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identity encap-ip-gach {
base bfd-types:encap-type;
description
"BFD with IP and G-ACh encapsulation as per RFC 5586.";
}
/*
* Groupings
*/
grouping encap-cfg {
description "Configuration for BFD encapsulation";
leaf encap {
type identityref {
base bfd-types:encap-type;
}
default bfd-types:encap-ip;
description "BFD encapsulation";
}
}
grouping mpls-dest-address {
description "Destination address as per RFC 5884.";
leaf mpls-dest-address {
type inet:ip-address;
config "false";
description
"Destination address as per RFC 5884.
Needed if IP encapsulation is used.";
}
}
/*
* Augments
*/
augment "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/bfd:bfd" {
description "BFD augmentation for MPLS.";
container mpls {
description "BFD MPLS top level container.";
uses bfd-types:session-statistics-summary;
container egress {
description "Egress configuration.";
uses bfd-types:client-cfg-parms;
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uses bfd-types:auth-parms;
}
container session-groups {
description
"BFD over MPLS session groups.";
list session-group {
key "mpls-fec";
description
"Group of BFD MPLS sessions (for ECMP). A group of " +
"sessions is for 1 FEC, each session has a different " +
"field in UDP/IP hdr for ECMP.";
leaf mpls-fec {
type inet:ip-prefix;
description "MPLS FEC.";
}
uses bfd-types:common-cfg-parms;
list sessions {
config false;
description
"The BFD sessions for an MPLS FEC. Local " +
"discriminator is unique for each session in the " +
"group.";
uses bfd-types:all-session;
uses bfd-mpls:mpls-dest-address;
}
}
}
}
}
/*
* Notifications
*/
notification mpls-notification {
description
"Notification for BFD over MPLS FEC session state change. " +
"An implementation may rate-limit notifications, e.g. when a " +
"session is continuously changing state.";
uses bfd-types:notification-parms;
leaf mpls-dest-address {
type inet:ip-address;
description
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"Destination address as per RFC 5884.
Needed if IP encapsulation is used.";
}
}
}
<CODE ENDS>
2.19. BFD over MPLS-TE YANG Module
This YANG module imports and augments "/te/tunnels/tunnel" from
[I-D.ietf-teas-yang-te].
<CODE BEGINS> file "ietf-bfd-mpls-te@2018-08-01.yang"
module ietf-bfd-mpls-te {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-bfd-mpls-te";
prefix "bfd-mpls-te";
// RFC Ed.: replace occurences of XXXX with actual RFC number and
// remove this note
import ietf-bfd-types {
prefix "bfd-types";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-bfd {
prefix "bfd";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-bfd-mpls {
prefix "bfd-mpls";
reference "RFC XXXX: YANG Data Model for BFD";
}
import ietf-te {
prefix "te";
// RFC Ed.: replace YYYY with actual RFC number of
// draft-ietf-teas-yang-te and remove this note.
reference
"RFC YYYY: A YANG Data Model for Traffic Engineering Tunnels and
Interfaces";
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}
import ietf-routing {
prefix "rt";
reference
"RFC 8349: A YANG Data Model for Routing Management
(NMDA version)";
}
organization "IETF BFD Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/bfd>
WG List: <rtg-bfd@ietf.org>
Editors: Reshad Rahman (rrahman@cisco.com),
Lianshu Zheng (vero.zheng@huawei.com),
Mahesh Jethanandani (mjethanandani@gmail.com)";
description
"This module contains the YANG definition for BFD parameters for
MPLS Traffic Engineering as per RFC 5884.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
reference "RFC XXXX";
revision 2018-08-01 {
description "Initial revision.";
reference "RFC XXXX: A YANG data model for BFD over MPLS-TE";
}
/*
* Augments
*/
augment "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/bfd:bfd" {
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description "BFD augmentation for MPLS-TE.";
container mpls-te {
description "BFD MPLS-TE top level container.";
container egress {
description "Egress configuration.";
uses bfd-types:client-cfg-parms;
uses bfd-types:auth-parms;
}
uses bfd-types:session-statistics-summary;
}
}
augment "/te:te/te:tunnels/te:tunnel" {
description "BFD configuration on MPLS-TE tunnel.";
uses bfd-types:common-cfg-parms;
uses bfd-mpls:encap-cfg;
}
augment "/te:te/te:lsps-state/te:lsp" {
when "/te:te/te:lsps-state/te:lsp/te:origin-type != 'transit'" {
description "BFD information not needed at transit points.";
}
description "BFD state information on MPLS-TE LSP.";
uses bfd-types:all-session;
uses bfd-mpls:mpls-dest-address;
}
/*
* Notifications
*/
notification mpls-te-notification {
description
"Notification for BFD over MPLS-TE session state change. " +
"An implementation may rate-limit notifications, e.g. when a " +
"session is continuously changing state.";
uses bfd-types:notification-parms;
uses bfd-mpls:mpls-dest-address;
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leaf tunnel-name {
type string;
description "MPLS-TE tunnel on which BFD was running.";
}
}
}
<CODE ENDS>
3. Data Model examples
This section presents some simple and illustrative examples on how to
configure BFD.
3.1. IP single-hop
The following is an example configuration for a BFD IP single-hop
session. The desired transmit interval and the required receive
interval are both set to 10ms.
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<?xml version="1.0" encoding="UTF-8"?>
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
<interface>
<name>eth0</name>
<type xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
ianaift:ethernetCsmacd
</type>
</interface>
</interfaces>
<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<control-plane-protocols>
<control-plane-protocol>
<type xmlns:bfd-types=
"urn:ietf:params:xml:ns:yang:ietf-bfd-types">
bfd-types:bfdv1
</type>
<name>name:BFD</name>
<bfd xmlns="urn:ietf:params:xml:ns:yang:ietf-bfd">
<ip-sh xmlns="urn:ietf:params:xml:ns:yang:ietf-bfd-ip-sh">
<sessions>
<session>
<interface>eth0</interface>
<dest-addr>2001:db8:0:113::101</dest-addr>
<desired-min-tx-interval>10000</desired-min-tx-interval>
<required-min-rx-interval>
10000
</required-min-rx-interval>
</session>
</sessions>
</ip-sh>
</bfd>
</control-plane-protocol>
</control-plane-protocols>
</routing>
</config>
3.2. IP multihop
The following is an example configuration for a BFD IP multihop
session group. The desired transmit interval and the required
receive interval are both set to 150ms.
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<?xml version="1.0" encoding="UTF-8"?>
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<control-plane-protocols>
<control-plane-protocol>
<type xmlns:bfd-types=
"urn:ietf:params:xml:ns:yang:ietf-bfd-types">
bfd-types:bfdv1
</type>
<name>name:BFD</name>
<bfd xmlns="urn:ietf:params:xml:ns:yang:ietf-bfd">
<ip-mh xmlns="urn:ietf:params:xml:ns:yang:ietf-bfd-ip-mh">
<session-groups>
<session-group>
<source-addr>2001:db8:0:113::103</source-addr>
<dest-addr>2001:db8:0:114::100</dest-addr>
<desired-min-tx-interval>
150000
</desired-min-tx-interval>
<required-min-rx-interval>
150000
</required-min-rx-interval>
<rx-ttl>240</rx-ttl>
</session-group>
</session-groups>
</ip-mh>
</bfd>
</control-plane-protocol>
</control-plane-protocols>
</routing>
</config>
3.3. LAG
The following is an example of BFD configuration for a LAG session.
In this case, an interface named "Bundle-Ether1" of interface type
"ieee802eadLag" has a desired transmit and required receive interval
set to 10ms.
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<?xml version="1.0" encoding="UTF-8"?>
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
<interface>
<name>Bundle-Ether1</name>
<type xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
ianaift:ieee8023adLag
</type>
</interface>
</interfaces>
<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<control-plane-protocols>
<control-plane-protocol>
<type xmlns:bfd-types=
"urn:ietf:params:xml:ns:yang:ietf-bfd-types">
bfd-types:bfdv1
</type>
<name>name:BFD</name>
<bfd xmlns="urn:ietf:params:xml:ns:yang:ietf-bfd">
<lag xmlns="urn:ietf:params:xml:ns:yang:ietf-bfd-lag">
<sessions>
<session>
<lag-name>Bundle-Ether1</lag-name>
<ipv6-dest-addr>2001:db8:112::16</ipv6-dest-addr>
<desired-min-tx-interval>
100000
</desired-min-tx-interval>
<required-min-rx-interval>
100000
</required-min-rx-interval>
<use-ipv6>true</use-ipv6>
</session>
</sessions>
</lag>
</bfd>
</control-plane-protocol>
</control-plane-protocols>
</routing>
</config>
3.4. MPLS
The following is an example of BFD configured for an MPLS LSP. In
this case, the desired transmit and required receive interval set to
250ms.
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<?xml version="1.0" encoding="UTF-8"?>
<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<control-plane-protocols>
<control-plane-protocol>
<type xmlns:bfd-types=
"urn:ietf:params:xml:ns:yang:ietf-bfd-types">
bfd-types:bfdv1
</type>
<name>name:BFD</name>
<bfd xmlns="urn:ietf:params:xml:ns:yang:ietf-bfd">
<mpls xmlns="urn:ietf:params:xml:ns:yang:ietf-bfd-mpls">
<session-groups>
<session-group>
<mpls-fec>2001:db8:114::/116</mpls-fec>
<desired-min-tx-interval>
250000
</desired-min-tx-interval>
<required-min-rx-interval>
250000
</required-min-rx-interval>
</session-group>
</session-groups>
</mpls>
</bfd>
</control-plane-protocol>
</control-plane-protocols>
</routing>
</config>
4. Security Considerations
The YANG module specified in this document defines a schema for data
that is designed to be accessed via network management protocols such
as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer
is the secure transport layer, and the mandatory-to-implement secure
transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer
is HTTPS, and the mandatory-to-implement secure transport is TLS
[RFC5246].
The NETCONF access control model [RFC6536] provides the means to
restrict access for particular NETCONF or RESTCONF users to a
preconfigured subset of all available NETCONF or RESTCONF protocol
operations and content.
There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the
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default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
to these data nodes without proper protection can have a negative
effect on network operations. These are the subtrees and data nodes
and their sensitivity/vulnerability:
/routing/control-plane-protocols/control-plane-protocol/bfd/ip-sh/
sessions: the list specifies the IP single-hop BFD sessions.
/routing/control-plane-protocols/control-plane-protocol/bfd/ip-sh/
sessions: data nodes local-multiplier, desired-min-tx-interval,
required-min-rx-interval and min-interval all impact the BFD IP
single-hop session. The source-addr and dest-addr data nodes can be
used to send BFD packets to unwitting recipients, [RFC5880] describes
how BFD mitigates against such threats. Authentication data nodes
key-chain and meticulous impact the security of the BFD IP single-hop
session.
/routing/control-plane-protocols/control-plane-protocol/bfd/ip-mh/
session-group: the list specifies the IP multi-hop BFD session
groups.
/routing/control-plane-protocols/control-plane-protocol/bfd/ip-mh/
session-group: data nodes local-multiplier, desired-min-tx-interval,
required-min-rx-interval and min-interval all impact the BFD IP
multi-hop session. The source-addr and dest-addr data nodes can be
used to send BFD packets to unwitting recipients, [RFC5880] describes
how BFD mitigates against such threats. Authentication data nodes
key-chain and meticulous impact the security of the BFD IP multi-hop
session.
/routing/control-plane-protocols/control-plane-protocol/bfd/lag/
sessions: the list specifies the BFD sessions over LAG.
/routing/control-plane-protocols/control-plane-protocol/bfd/lag/
sessions: data nodes local-multiplier, desired-min-tx-interval,
required-min-rx-interval and min-interval all impact the BFD over LAG
session. The ipv4-dest-addr and ipv6-dest-addr data nodes can be
used to send BFD packets to unwitting recipients, [RFC5880] describes
how BFD mitigates against such threats. Authentication data nodes
key-chain and meticulous impact the security of the BFD over LAG
session.
/routing/control-plane-protocols/control-plane-protocol/bfd/mpls/
session-group: the list specifies the session groups for BFD over
MPLS.
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/routing/control-plane-protocols/control-plane-protocol/bfd/mpls/
session-group: data nodes local-multiplier, desired-min-tx-interval,
required-min-rx-interval, and min-interval all impact the BFD over
MPLS LSPs session. Authentication data nodes key-chain and
meticulous impact the security of the BFD over MPLS LSPs session.
/routing/control-plane-protocols/control-plane-protocol/bfd/mpls/
egress: data nodes local-multiplier, desired-min-tx-interval,
required-min-rx-interval and min-interval all impact the BFD over
MPLS LSPs sessions for which this device is an MPLS LSP egress node.
Authentication data nodes key-chain and meticulous impact the
security of the BFD over MPLS LSPs sessions for which this device is
an MPLS LSP egress node
/te/tunnels/tunnel: data nodes local-multiplier, desired-min-tx-
interval, required-min-rx-interval and min-interval all impact the
BFD session over the MPLS-TE tunnel. Authentication data nodes key-
chain and meticulous impact the security of the BFD session over the
MPLS-TE tunnel.
/routing/control-plane-protocols/control-plane-protocol/bfd/mpls-te/
egress: data nodes local-multiplier, desired-min-tx-interval,
required-min-rx-interval and min-interval all impact the BFD over
MPLS-TE sessions for which this device is an MPLS-TE egress node.
Authentication data nodes key-chain and meticulous impact the
security of the BFD over MPLS-TE sessions for which this device is an
MPLS-TE egress node.
The YANG module has writeable data nodes which can be used for
creation of BFD sessions and modification of BFD session parameters.
The system should "police" creation of BFD sessions to prevent new
sessions from causing existing BFD sessions to fail. For BFD session
modification, the BFD protocol has mechanisms in place which allow
for in service modification.
When BFD clients are used to modify BFD configuration (as described
in Section 2.1), the BFD clients need to be included in an analysis
of the security properties of the BFD-using system (e.g., when
considering the authentication and authorization of control actions).
In many cases, BFD is not the most vulnerable portion of such a
composite system, since BFD is limited to generating well-defined
traffic at a fixed rate on a given path; in the case of an IGP as BFD
client, attacking the IGP could cause more broad-scale disruption
than (de)configuring a BFD session could cause.
Some of the readable data nodes in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control read access (e.g., via get, get-config, or
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notification) to these data nodes. These are the subtrees and data
nodes and their sensitivity/vulnerability:
/routing/control-plane-protocols/control-plane-protocol/bfd/ip-sh/
summary: access to this information discloses the number of BFD IP
single-hop sessions which are up, down and admin-down. The counters
include BFD sessions for which the user does not have read-access.
/routing/control-plane-protocols/control-plane-protocol/bfd/ip-
sh/sessions/session/: access to data nodes local-discriminator and
remote-discriminator (combined with the data nodes in the
authentication container) provides the ability to spoof BFD IP
single-hop packets.
/routing/control-plane-protocols/control-plane-protocol/bfd/ip-mh/
summary: access to this information discloses the number of BFD IP
multi-hop sessions which are up, down and admin-down. The counters
include BFD sessions for which the user does not have read-access.
/routing/control-plane-protocols/control-plane-protocol/bfd/ip-mh/
session-groups/session-group/sessions: access to data nodes local-
discriminator and remote-discriminator (combined with the data nodes
in the session-group's authentication container) provides the ability
to spoof BFD IP multi-hop packets.
/routing/control-plane-protocols/control-plane-protocol/bfd/lag/
micro-bfd-ipv4-session-statistics/summary: access to this information
discloses the number of micro BFD IPv4 LAG sessions which are up,
down and admin-down. The counters include BFD sessions for which the
user does not have read-access.
/routing/control-plane-protocols/control-plane-
protocol/bfd/lag/sessions/session/member-links/member-link/micro-bfd-
ipv4: access to data nodes local-discriminator and remote-
discriminator (combined with the data nodes in the session's
authentication container) provides the ability to spoof BFD IPv4 LAG
packets.
/routing/control-plane-protocols/control-plane-protocol/bfd/lag/
micro-bfd-ipv6-session-statistics/summary: access to this information
discloses the number of micro BFD IPv6 LAG sessions which are up,
down and admin-down. The counters include BFD sessions for which the
user does not have read-access.
/routing/control-plane-protocols/control-plane-
protocol/bfd/lag/sessions/session/member-links/member-link/micro-bfd-
ipv6: access to data nodes local-discriminator and remote-
discriminator (combined with the data nodes in the session's
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authentication container) provides the ability to spoof BFD IPv6 LAG
packets.
/routing/control-plane-protocols/control-plane-protocol/bfd/mpls/
summary: access to this information discloses the number of BFD
sessions over MPLS LSPs which are up, down and admin-down. The
counters include BFD sessions for which the user does not have read-
access.
/routing/control-plane-protocols/control-plane-protocol/bfd/mpls/
session-groups/session-group/sessions: access to data nodes local-
discriminator and remote-discriminator (combined with the data nodes
in the session-group's authentication container) provides the ability
to spoof BFD over MPLS LSPs packets.
/routing/control-plane-protocols/control-plane-protocol/bfd/mpls-te/
summary: access to this information discloses the number of BFD
sessions over MPLS-TE which are up, down and admin-down. The
counters include BFD sessions for which the user does not have read-
access.
/te/lsps-state/lsp: access to data nodes local-discriminator and
remote-discriminator (combined with the data nodes in the tunnel's
authentication container) provides the ability to spoof BFD over
MPLS-TE packets.
5. IANA Considerations
This document registers the following namespace URIs in the IETF XML
registry [RFC3688]:
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:iana-bfd-types
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-bfd-types
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
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--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-bfd
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-bfd-ip-sh
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-bfd-mh
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-bfd-lag
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-bfd-mpls
Registrant Contact: The IESG.
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XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-bfd-mpls-te
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
This document registers the following YANG modules in the YANG Module
Names registry [RFC6020]:
RFC Editor: Replace RFC XXXX with actual RFC number and remove this
note.
--------------------------------------------------------------------
Name: iana-bfd-types
Namespace: urn:ietf:params:xml:ns:yang:iana-bfd-types
Prefix: iana-bfd-types
Reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
Name: ietf-bfd-types
Namespace: urn:ietf:params:xml:ns:yang:ietf-bfd-types
Prefix: bfd-types
Reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
Name: ietf-bfd
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Namespace: urn:ietf:params:xml:ns:yang:ietf-bfd
Prefix: bfd
Reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
Name: ietf-bfd-ip-sh
Namespace: urn:ietf:params:xml:ns:yang:ietf-bfd-ip-sh
Prefix: bfd-ip-sh
Reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
Name: ietf-bfd-ip-mh
Namespace: urn:ietf:params:xml:ns:yang:ietf-bfd-ip-mh
Prefix: bfd-ip-mh
Reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
Name: ietf-bfd-lag
Namespace: urn:ietf:params:xml:ns:yang:ietf-bfd-lag
Prefix: bfd-lag
Reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
Name: ietf-bfd-mpls
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Namespace: urn:ietf:params:xml:ns:yang:ietf-bfd-mpls
Prefix: bfd-mpls
Reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
Name: ietf-bfd-mpls-te
Namespace: urn:ietf:params:xml:ns:yang:ietf-bfd-mpls-te
Prefix: bfd-mpls-te
Reference: RFC XXXX
--------------------------------------------------------------------
5.1. IANA-Maintained iana-bfd-types module
This document defines the initial version of the IANA-maintained
iana-bfd-types YANG module.
The iana-bfd-types YANG module mirrors the "BFD Diagnostic Codes"
registry and "BFD Authentication Types" registry at
https://www.iana.org/assignments/bfd-parameters/bfd-parameters.xhtml.
Whenever that registry changes, IANA must update the iana-bfd-types
YANG module.
6. Acknowledgements
We would also like to thank Nobo Akiya and Jeff Haas for their
encouragement on this work. We would also like to thank Rakesh
Gandhi and Tarek Saad for their help on the MPLS-TE model. We would
also like to thank Acee Lindem for his guidance.
7. References
7.1. Normative References
[I-D.ietf-mpls-base-yang]
Saad, T., Raza, K., Gandhi, R., Liu, X., and V. Beeram, "A
YANG Data Model for MPLS Base", draft-ietf-mpls-base-
yang-06 (work in progress), February 2018.
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[I-D.ietf-teas-yang-te]
Saad, T., Gandhi, R., Liu, X., Beeram, V., Shah, H., and
I. Bryskin, "A YANG Data Model for Traffic Engineering
Tunnels and Interfaces", draft-ietf-teas-yang-te-16 (work
in progress), July 2018.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/info/rfc5246>.
[RFC5586] Bocci, M., Ed., Vigoureux, M., Ed., and S. Bryant, Ed.,
"MPLS Generic Associated Channel", RFC 5586,
DOI 10.17487/RFC5586, June 2009,
<https://www.rfc-editor.org/info/rfc5586>.
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
<https://www.rfc-editor.org/info/rfc5880>.
[RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881,
DOI 10.17487/RFC5881, June 2010,
<https://www.rfc-editor.org/info/rfc5881>.
[RFC5882] Katz, D. and D. Ward, "Generic Application of
Bidirectional Forwarding Detection (BFD)", RFC 5882,
DOI 10.17487/RFC5882, June 2010,
<https://www.rfc-editor.org/info/rfc5882>.
[RFC5883] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD) for Multihop Paths", RFC 5883, DOI 10.17487/RFC5883,
June 2010, <https://www.rfc-editor.org/info/rfc5883>.
[RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow,
"Bidirectional Forwarding Detection (BFD) for MPLS Label
Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884,
June 2010, <https://www.rfc-editor.org/info/rfc5884>.
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[RFC5885] Nadeau, T., Ed. and C. Pignataro, Ed., "Bidirectional
Forwarding Detection (BFD) for the Pseudowire Virtual
Circuit Connectivity Verification (VCCV)", RFC 5885,
DOI 10.17487/RFC5885, June 2010,
<https://www.rfc-editor.org/info/rfc5885>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model", RFC 6536,
DOI 10.17487/RFC6536, March 2012,
<https://www.rfc-editor.org/info/rfc6536>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7130] Bhatia, M., Ed., Chen, M., Ed., Boutros, S., Ed.,
Binderberger, M., Ed., and J. Haas, Ed., "Bidirectional
Forwarding Detection (BFD) on Link Aggregation Group (LAG)
Interfaces", RFC 7130, DOI 10.17487/RFC7130, February
2014, <https://www.rfc-editor.org/info/rfc7130>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8177] Lindem, A., Ed., Qu, Y., Yeung, D., Chen, I., and J.
Zhang, "YANG Data Model for Key Chains", RFC 8177,
DOI 10.17487/RFC8177, June 2017,
<https://www.rfc-editor.org/info/rfc8177>.
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[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>.
[RFC8344] Bjorklund, M., "A YANG Data Model for IP Management",
RFC 8344, DOI 10.17487/RFC8344, March 2018,
<https://www.rfc-editor.org/info/rfc8344>.
[RFC8349] Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
Routing Management (NMDA Version)", RFC 8349,
DOI 10.17487/RFC8349, March 2018,
<https://www.rfc-editor.org/info/rfc8349>.
7.2. Informative References
[I-D.ietf-lime-yang-connectionless-oam]
Kumar, D., Wang, Z., Wu, Q., Rahman, R., and S. Raghavan,
"Generic YANG Data Model for the Management of Operations,
Administration, and Maintenance (OAM) Protocols that use
Connectionless Communications", draft-ietf-lime-yang-
connectionless-oam-18 (work in progress), November 2017.
[I-D.ietf-rtgwg-lne-model]
Berger, L., Hopps, C., Lindem, A., Bogdanovic, D., and X.
Liu, "YANG Model for Logical Network Elements", draft-
ietf-rtgwg-lne-model-10 (work in progress), March 2018.
[I-D.ietf-rtgwg-ni-model]
Berger, L., Hopps, C., Lindem, A., Bogdanovic, D., and X.
Liu, "YANG Model for Network Instances", draft-ietf-rtgwg-
ni-model-12 (work in progress), March 2018.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
Appendix A. Echo function configuration example
As mentioned in Section 2.1.2, the mechanism to start and stop the
echo function, as defined in [RFC5880] and [RFC5881], is
implementation specific. In this section we provide an example of
how the echo function can be implemented via configuration.
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module: example-bfd-echo
augment /rt:routing/rt:control-plane-protocols
/rt:control-plane-protocol/bfd:bfd/bfd-ip-sh:ip-sh
/bfd-ip-sh:sessions:
+--rw echo {bfd-types:echo-mode}?
+--rw desired-min-echo-tx-interval? uint32
+--rw required-min-echo-rx-interval? uint32
A.1. Example YANG module for BFD echo function configuration
module example-bfd-echo {
namespace "tag:example.com,2018:example-bfd-echo";
prefix "example-bfd-echo";
import ietf-bfd-types {
prefix "bfd-types";
}
import ietf-bfd {
prefix "bfd";
}
import ietf-bfd-ip-sh {
prefix "bfd-ip-sh";
}
import ietf-routing {
prefix "rt";
}
organization "IETF BFD Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/bfd>
WG List: <rtg-bfd@ietf.org>
Editors: Reshad Rahman (rrahman@cisco.com),
Lianshu Zheng (vero.zheng@huawei.com),
Mahesh Jethanandani (mjethanandani@gmail.com)";
description
"This module contains an example YANG augmentation for configuration
of BFD echo function.
Copyright (c) 2018 IETF Trust and the persons
identified as authors of the code. All rights reserved.
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Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2018-08-01 {
description "Initial revision.";
reference
"RFC XXXX: A YANG data model example augmentation for BFD echo
function";
}
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note
/*
* Groupings
*/
grouping echo-cfg-parms {
description "BFD grouping for echo config parameters";
leaf desired-min-echo-tx-interval {
type uint32;
units microseconds;
default 0;
description
"This is the minimum interval that the local system would like
to use when transmitting BFD echo packets. If 0, the echo
function as defined in BFD [RFC5880] is disabled.";
}
leaf required-min-echo-rx-interval {
type uint32;
units microseconds;
default 0;
description
"This is the Required Min Echo RX Interval as defined in BFD
[RFC5880].";
}
}
augment "/rt:routing/rt:control-plane-protocols/"
+ "rt:control-plane-protocol/bfd:bfd/bfd-ip-sh:ip-sh/"
+ "bfd-ip-sh:sessions" {
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description "Augmentation for BFD echo function.";
container echo {
if-feature bfd-types:echo-mode;
description "BFD echo function container";
uses echo-cfg-parms;
}
}
}
Appendix B. Change log
RFC Editor: Remove this section upon publication as an RFC.
B.1. Changes between versions -16 and -17
o Addressed IESG comments.
B.2. Changes between versions -15 and -16
o Added list of modules for YANG module registry.
B.3. Changes between versions -14 and -15
o Added missing ietf-bfd-types in XML registry.
B.4. Changes between versions -13 and -14
o Addressed missing/incorrect references in import statements.
B.5. Changes between versions -12 and -13
o Updated references for drafts which became RFCs recently.
B.6. Changes between versions -11 and -12
o Addressed comments from YANG Doctor review of rev11.
B.7. Changes between versions -10 and -11
o Added 2 examples.
o Added a container around some lists.
o Fixed some indentation nits.
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B.8. Changes between versions -09 and -10
o Addressed comments from YANG Doctor review.
o Addressed comments from WGLC.
B.9. Changes between versions -08 and -09
o Mostly cosmetic changes to abide by draft-ietf-netmod-rfc6087bis.
o Specified yang-version 1.1.
o Added data model examples.
o Some minor changes.
B.10. Changes between versions -07 and -08
o Timer intervals in client-cfg-parms are not mandatory anymore.
o Added list of interfaces under "ip-sh" node for authentication
parameters.
o Renamed replay-protection to meticulous.
B.11. Changes between versions -06 and -07
o New ietf-bfd-types module.
o Grouping for BFD clients to have BFD multiplier and interval
values.
o Change in ietf-bfd-mpls-te since MPLS-TE model changed.
o Removed bfd- prefix from many names.
B.12. Changes between versions -05 and -06
o Adhere to NMDA-guidelines.
o Echo function config moved to appendix as example.
o Added IANA YANG modules.
o Addressed various comments.
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B.13. Changes between versions -04 and -05
o "bfd" node in augment of control-plane-protocol.
o Removed augment of network-instance. Replaced by schema-mount.
o Added information on interaction with other YANG modules.
B.14. Changes between versions -03 and -04
o Updated author information.
o Fixed YANG compile error in ietf-bfd-lag.yang which was due to
incorrect when statement.
B.15. Changes between versions -02 and -03
o Fixed YANG compilation warning due to incorrect revision date in
ietf-bfd-ip-sh module.
B.16. Changes between versions -01 and -02
o Replace routing-instance with network-instance from YANG Network
Instances [I-D.ietf-rtgwg-ni-model]
B.17. Changes between versions -00 and -01
o Remove BFD configuration parameters from BFD clients, all BFD
configuration parameters in BFD
o YANG module split in multiple YANG modules (one per type of
forwarding path)
o For BFD over MPLS-TE we augment MPLS-TE model
o For BFD authentication we now use YANG Data Model for Key Chains
[RFC8177]
Authors' Addresses
Reshad Rahman (editor)
Cisco Systems
Canada
Email: rrahman@cisco.com
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Lianshu Zheng (editor)
Huawei Technologies
China
Email: vero.zheng@huawei.com
Mahesh Jethanandani (editor)
Xoriant Corporation
1248 Reamwood Ave
Sunnyvale, California 94089
USA
Email: mjethanandani@gmail.com
Santosh Pallagatti
Rtbrick
India
Email: santosh.pallagatti@gmail.com
Greg Mirsky
ZTE Corporation
Email: gregimirsky@gmail.com
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