[c-nsp] FIB scale on ASR9001

[Mark Tinka]

On 11/11/21 09:51, Gert Doering wrote:

> I seem to remember it's related to RPKI ROV (every time the RPKI server
> sends new data the BGP implementation asks for a refresh to re-validate
> the incoming feed).
>
> Or at least there is something in the back of my head that says "I have
> heard someone talk about this unintended side-effect of RPKI ROV, together
> with a BGP setup without 'soft in always'".
>
> Might there be a correlation in your environment?

Yes, this makes sense.

We, generally, did not run "soft-reconfiguration inbound" since the IOS 
days, to save on RAM. Also, Route Refresh was the gold standard. I'm not 
sure the RAM issue is a big deal anymore, considering how large it is in 
routers these days...

But I can see how this creates an undesired side effect with ROV, which 
then puts pressure on Route Refresh.

I have to say, we did not consider it; which hardly surprises me since 
TAC didn't either.

I have read a lot of Cisco documentation on configuring ROV on IOS XE 
and IOS XR, and unless something has been recently updated, this is not 
one of the explicit recommendations in that documentation. I can see how 
easy it is to overlook (or if you do have 'soft-reconfiguration inbound' 
configured, how that significance can also be overlooked).

All that notwithstanding, the move to 100Gbps peering/transit + faster 
CPU's on the MX204 is still a worthy reason to move away from the 
ASR9001, for us anyway :-).

Mark.