IOS-XR RPL Scale

[Johnny Karms Pedersen]

Hi,

To what extent does the ASR9K RPL scale when it comes to number of entries in a single route-policy?

My question is based on a possible migration of an Inter-AS MPLS Option A POI to Option B an requiring a large number of 1:1 RT rewrites.

Any upper limits (although this being handled in control-plane), guidelines, etc.?

TIA.

Johnny

[xthuijs · Accepted solution]

hi johnny,

there is no limit in that regard. it can get as long as it needs to be.

obviously the execution time varies when you have a large rpl.

But this time is measured in usecs.

As in terms of optimization:

things like if as-path in (A or B or C) executes faster then when you have a as-path-set with A/B/C and you call it like if as-path in <prefix-set>.

another one is if'ing:

if this then

endif

if somethingelse then

endif

is slower because every if is evaluated whereby the:

if this then

elseif something else then

endif

goes faster because we can stop branching if we matched the first if.

but here also, it is all measured in usec execution.

RPL "compiles" the policy and sends it down to the application, eg BGP. So BGP holds a compiled repository from RPL. It is not that BGP will query RPL for the verification hence it being so fast

regards

xander

[Johnny Karms Pedersen]

Hi Xander,

Thanks for the swift reply! :)

- Johnny