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

Mikael Abrahamsson swmike at swm.pp.se
Mon Sep 14 17:39:12 UTC 2009

On Mon, 14 Sep 2009, Michael Ruiz wrote:

> I am having difficulty maintaining my BGP session from my 6509 with
> Sup-7203bxls to a 7206 VXR NPE-400.  The session bounces every 3
> minutes.  I do have other IBGP sessions that are established with no
> problems, however, this is the only IBGP peer that is bouncing
> regularly.
> What does exactly the message mean and how do I stabilize this?  Any
> help will be appreciated.

This is most likely an MTU problem. Your SYN/SYN+ACK goes thru, but then 
the first fullsize MSS packet is sent, and it's not getting to the 
destination. 3 minutes is the dead timer for keepalives, which are not 
getting thru either because of the stalled TCP session.

Mikael Abrahamsson    email: swmike at swm.pp.se

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