[Linux-cluster] >1500 MTU on EL5 causes things to go sideways

[Digimer]

Hi all,

  I've got a two-node EL5.6 cluster with a handful of interfaces on the
nodes. When I do not specify MTU=x, everything works great. However, I
want to use jumbo frames, and so the fun begins.

  As soon as I define MTU=2000 (for example), then cman on one note will
start but not stop (the other node stops fine). Also, 'ccs_tool update
/etc/cluster/cluster.conf' fails with:

====
[root at xenmaster003 ~]# ccs_tool update /etc/cluster/cluster.confFailed
to receive COMM_UPDATE_NOTICE_ACK from xenmaster004.iplink.net.
Hint: Check the log on xenmaster004.iplink.net for reason.

Failed to update config file.
====

  Nothing at all gets written to the target node's log files though.

  Is there some subtle magic needed to get jumbo frames working in the
cluster? Am I missing the forest for the trees? :)

-- 
Digimer
E-Mail: digimer at alteeve.com
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