[c-nsp] ASR9k LC fib programming problem

[James Bensley]

On 13 July 2017 at 16:02, Šturmankin Miroslav
<miroslav.sturmankin at swan.sk> wrote:
> router specifications:
> ASR9006 IOS XR 4.3.4 SP4
> A9K-RSP-4G
> A9K-MOD160-TR + A9K-MPA-8X10GE & A9K-MPA-4X10GE

That is a an old IOS-XR version which I urge you to upgrade from, it's
full of bugs, as you can see, I suggest you upgrade and the problem
with probably go away.

Have you tried to restart the IPV4 RIB process? "process restart ipv4_rib"

That should cause the route to be re-downloaded to the card when the
process restarts without a forwarding interruption. It won't clear
routes from the card but when the process starts up again it will
check what is on the card vs. what is in the central FIB and reprogram
any miss-matches. We had a race condition on 4.3.4 [default through to
SP4] with Inter-AS L3VPN routes not being programmed into the line
card when there was a next-hop change, restarting that process
sometimes fixed the problem.

If you route is also a labelled entriy you can try "process restart
mpls_lsd" which will have same affect as above, if the label is wrong
in a route when the process starts up again it should re-program the
route into the line card.

You said you have cleared the route from the line card but that didn't
worked, can you arrange a maintenance window and clear the entire CEF
table on the card? "clear cef linecard location 0/1/CPU0" that will
cause a "blip" outage as all routes are dropped from the card and then
re-programmed.

Really though, in my opinion, an XR upgrade is needed here as the long term fix.

Cheers,
James.