[HPDD-discuss] MDS failover issue

Hi all, running Lustre 2.5.3, we have two MDSes at 10.20.0.25@o2ib1 and 10.20.0.20@o2ib1, accessing some shared storage. On 10.20.0.25, I have formatted an MGS and MDT with and Both mounted cleanly. On an OSS, I formatted an OST Mounted cleanly, as did the fs on a client. Then I umounted both MDT and MGS on 10.20.0.25 and mounted them on the failover 10.20.0.20. This seems to have worked, although ptlrpc_expire_one_request() keeps complaining about network errors which only mention the 'dead' nid 10.20.0.25@o2ib1. But the log also states and the listing /proc/fs/lustre/devices is complete. That is, also the OSS reconnected, its log says This seems to be o.k. However the client is stuck. Its log shows the same two messages, but followed by Correspondingly, there is no Lustre access on this client, I have of course played around with the specification of nids on the mkfs-commandline, colon-separated statement of mgsnodes, adding both nids as servicenodes to the MGS-format, - nada. The only Jira I could find for this error message "mgc: cannot find uuid by nid" is LU-5950. This has "Fix Version/s: Lustre 2.7.0" - no failover prior to that? - hard to believe ;-) Any idea where I messed up? Thanks, Thomas -- -------------------------------------------------------------------- Thomas Roth IT-HPC-Linux Location: SB3 1.262 Phone: +49-6159-71 1453 http://twitter.com/gsi_it