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Re: [Xen-devel] ARP cache problems / slow connect times in routed mode -

To: Matt Ayres <matta@xxxxxxxxxxxx>
Subject: Re: [Xen-devel] ARP cache problems / slow connect times in routed mode - Bug #596 opened
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Sat, 1 Apr 2006 17:56:27 +0100
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On 1 Apr 2006, at 17:05, Matt Ayres wrote:

A user of mine has debugged this issue for me. It seems a Xen guest in routed mode wants to arp cache any host it connects to with the MAC address FE:FF:FF:FF:FF:FF. The user also identified long connection times due to this. While a remote host is in the arp cache connection times are fast (30ms or so), when it is not it can be well over 1000ms. They have provided me the tcpdump output that proves this. They also proved it is due to the ARP cache by statically adding a remote host to the ARP cache and noting that connection times are very low.
Full debugging information is attached to the bug.
Bug URL: http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=596

I have assigned this by to myself and marked it as INVALID. It appears to be specific to CentOS / Fedora and my specific setup.

We'll be interested to learn the full details if you manage to work out what's going on. :-)

 -- Keir

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