[c-nsp] RPF on 6500

[Tim Stevenson]

At 06:08 AM 5/22/2005, RawCode gushed:
>Is there a performance difference between the two methods (rx | any)
>of turning on RPF on a 6500?

No, same performance impact (ie, none). Do note that you can't mix/match 
modes on different i/fs, all i/fs use the last configured mode, strict or 
loose.

>  Also is there a performance hit if you
>enable an access-list for the RPF?

Yes, softwware performance - this is not supported in the h/w.

>   How would this compare to just
>using an access-grouped interface?

access-group gets h/w enforcement, so the choice is clear...

>The 6500 is currently using 12.1(23) with a Sup2 and PFC2 and MSFC2.

Note that enabling uRPF check on sup2/pfc2 halves your total available FIB 
TCAM.

>I understand that the PFC2 will handle packets that have a single
>return path, and any others will be passed onto the MSFC2.

In strict mode, yes, that's correct.

Tim


>This
>shouldn't be too much of an issue since the 6500 is acting as our
>aggregation point for dsl and dial platforms so it is a pretty single
>path environment.
>
>TIA!
>
>Mike Gonnason
>
>_______________________________________________
>cisco-nsp mailing list  cisco-nsp at puck.nether.net
>https://puck.nether.net/mailman/listinfo/cisco-nsp
>archive at http://puck.nether.net/pipermail/cisco-nsp/



Tim Stevenson, tstevens at cisco.com
Routing & Switching CCIE #5561
Technical Marketing Engineer, Catalyst 6500
Cisco Systems, http://www.cisco.com
IP Phone: 408-526-6759
********************************************************
The contents of this message may be *Cisco Confidential*
and are intended for the specified recipients only.