<Keepalives are temporarily in throttle due to closed TCP window>

Richard A Steenbergen ras at e-gerbil.net
Tue Sep 15 20:31:19 UTC 2009

On Tue, Sep 15, 2009 at 03:10:52PM -0500, Michael Ruiz wrote:
> Below is snap shot of the neighbor in question.
> Datagrams (max data segment is 4410 bytes):
> Rcvd: 6 (out of order: 0), with data: 4, total data bytes: 278
> Sent: 6 (retransmit: 5), with data: 2, total data bytes: 4474
> Could there be a problem with the total data bytes size exceeds the size
> of the max data segment?

The maximum BGP message size is 4096 and there is no padding, so you
would need a heck of a lot of overhead to get another 300+ bytes on
there. I'd say the answer is no, unless you're running this over a MPLS
over GRE over MPLS over IPSec over MPLS over... well... you get the
picture. :)

It's possible that your link isn't actually capable of passing 4096-ish 
byte packets for whatever resaon. A quick way to validate or eliminate 
that theory is to do some pings from the router with different size 
payloads, sourced from your side of the /30 and pinging the far side, 
and using the df-bit to prevent fragmentation. Failing that, make sure 
you aren't doing anything stupid with your control plane policiers, 
maybe try turning those off to see if there is an improvement.

Richard A Steenbergen <ras at e-gerbil.net>       http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)

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