On 04/12/2011 11:16 AM, Gordan Bobic wrote: > Digimer wrote: > >> 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@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? :) > > This may be a silly question, but as a first pass: No worries, I routinely make silly mistakes, so silly questions are appropriate. :) > 1) Do you have the MTU set on both nodes to the same value at the same > time? Yes. > 2) Have you confirmed that your NICs actually work properly with jumbo > frames? Some Gb NICs can't handle them. Yes. > 3) Does your switch support jumbo frames and have you explicitly enabled > them on the switch? Yes and yes. > I have used jumbo frames up to 16KB (on Intel NICs with a cross-over > cable on a 2-node cluster) with no problems. > > Gordan Thanks for the questions. Still answer-hunting though. :P -- Digimer E-Mail: digimer@xxxxxxxxxxx AN!Whitepapers: http://alteeve.com Node Assassin: http://nodeassassin.org -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
