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<div class="moz-cite-prefix">On 16/Jul/20 19:34, Mark Tinka wrote:<br>
<br>
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cite="mid:35eb196f-a83b-b92c-1c7c-66b258c900a6@seacom.com">
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<font face="Tahoma">BFD on LAG's on IOS XR platforms in a LAN
environment don't work. A point-to-point mechanism is required,
so we disabled it there. Junos and IOS XE have no problems
running BFD on LAG's in LAN's, so we have it on there. This is
for within the data centre.<br>
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<br>
So for the archives, I thought I'd update this comment in case
anyone comes across this issue in the future.<br>
<br>
If you want to run BFD on a LAG in IOS XR, you need to tell it to do
so with the below command:<br>
<br>
conf <br>
bfd<br>
mutlipath include location <location-id><br>
<br>
This ensures that at least one physical line card (where a member
link may live) hosts the BFD sessions. Without this, the router
tries to host the session on the RP, which doesn't work. This also
applies to fixed form factor IOS XR-based routers.<br>
<br>
In previous versions of IOS XR, enabling BFD without this feature
simply kept the BFD sessions down. At some point (not sure when, but
we saw this in 6.7.1), IS-IS will remain down if BFD remains down,
i.e., having this command is now mandatory. <br>
<br>
The error log to signal you to this requirement is not particularly
user-friendly:<br>
<br>
%L2-BFD-6-SESSION_NO_RESOURCES<br>
<br>
We won't be messing around with BFD on LAG's in IOS XR still, as a
matter of course. Too many moving parts compared to how it's done in
Junos.<br>
<br>
But for anyone who may need this, here you go.<br>
<br>
Mark.<br>
<br>
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