Re: [OSPF] IETF OSPF YANG and BFD Configuration

Mahesh Jethanandani <> Thu, 18 May 2017 21:39 UTC

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From: Mahesh Jethanandani <>
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Date: Thu, 18 May 2017 14:33:07 -0700
Cc: Jeffrey Haas <>, OSPF WG List <>, "" <>, "" <>, "" <>
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To: "Acee Lindem (acee)" <>
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Subject: Re: [OSPF] IETF OSPF YANG and BFD Configuration
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Agree with Acee’s assessment. After much debate, we decided that we should leave BFD parameter configuration in the BFD model itself, and have any IGP protocol reference the BFD instance in BFD itself. This makes sense specially if multiple protocols fate-share the BFD session.


> On May 18, 2017, at 12:27 PM, Acee Lindem (acee) <> wrote:
> Hi Jeff, 
> At the OSPF WG Meeting in Chicago, you suggested that we may want to provide configuration of BFD parameters within the OSPF model (ietf-ospf.yang). We originally did have this configuration. However, after much discussion and coordination with the BFD YANG design team, we agreed to leave the BFD session parameters in BFD and only enable BFD within the OSPF and IS-IS models. 
> We did discuss the fact that vendors (notably Cisco IOS-XR and Juniper JUNOS) do allow configuration within the IGPs. However, the consensus was to leave the BFD configuration in the BFD model. The heuristics to determine what parameters to use when the same BFD endpoint was configured with different parameters in different protocols were proprietary and somewhat of a hack. 
> I may have not remembered all the details so I’d encourage others to chime in. 
> Thanks,
> Acee 

Mahesh Jethanandani