[c-nsp] slow convergence for full bgp table on a Cisco 7613/SUP720-3BXL

[Emanuel Popa]

Hi Gert,

We have no packet loss on the 10GE interfaces. We are using
control-plane policing but everything is configured properly. One of
the upgrades has been made using old IP addresses, so no change had to
be made in the access-lists used on the control plane.

I have attached an image with the cpu load graphs. The 5 min. averages
look good. But the 5 sec. averages look pretty bad. It has been like
this since we installed it and Cisco said it is not a carrier class
equipment and it was not built to hold as many bgp sessions with as
many prefixes. Also we are using control-plane policing. If we
wouldn't use it the IGP neighbors would flap a lot. Also we are
rate-limiting the TTL invalid packets because the traceroutes going
through this machine were overloading the RP CPU.

Thanks,
Emanuel


On 3/13/07, Gert Doering <gert at greenie.muc.de> wrote:
> Hi,
>
> On Tue, Mar 13, 2007 at 03:50:32PM +0200, Emanuel Popa wrote:
> > we had 2 x GE links with our upstream and one BGP session with full
> > routing table on the loopback interfaces. everything was fine until we
> > needed an upgrade. so we upgraded from 2 x GE to 1 x 10GE. our biggest
> > issue is that our router needs around two hours to receive the full
> > bgp table over the new session. the old session takes a maximum of
> > five minutes to converge. the only difference is that one session ends
> > on a 6724-SFP linecard and the other session ends on a 6704-10GE
> > linecard. both of them have DFCs.
>
> Do you have packet loss on the new 10GE line?  Or do you happen to
> rate-limit (control plane policing) your BGP session?
>
> If you see high CPU load, which process is causing it ("show proc cpu sort")?
>
> Normally the type of line card should not have any effect on control
> plane traffic, i.e. BGP.
>
> gert
> --
> USENET is *not* the non-clickable part of WWW!
>                                                            //www.muc.de/~gert/
> Gert Doering - Munich, Germany                             gert at greenie.muc.de
> fax: +49-89-35655025                        gert at net.informatik.tu-muenchen.de
>