Red Hat Bugzilla – Bug 195502
Regression: cluster mirror creation cmd hangs even though mirror gets created
Last modified: 2007-11-30 17:07:25 EST
Description of problem: With the latest built cmirror rpms an attempt to create a clustered mirror hangs. There doesn't appear to be any sync issues, or any off by one error, and the mirror appears to be completely created and in sync from the cluster's point of view, it's just that the actual cmd to create the mirror never returns. Version-Release number of selected component (if applicable): [root@taft-03 ~]# rpm -q cmirror cmirror-1.0.0-5 [root@taft-03 ~]# rpm -q cmirror-kernel cmirror-kernel-2.6.9-5.4
This is the kernel bug that I will be posting a patch for soon. After the device is created, lvcreate will attempt to zero out the first bunch of blocks on the device. Doing this will cause writes to colide with resync'ing regions. This causes a hang in the 2.6.9-39.EL kernel. To test and see that this is the bug I think it is, you can do 'lvcreate --nosync ...' and you should not see the hang on lvcreate. This is because --nosync says that it will not initially re-sync the mirror - meaning there can be no colision.
This hang does not happen when using the --nosync on creation.
please retest with kernel > 39.EL
committed in stream U4 build 39.2. A test kernel with this patch is available from http://people.redhat.com/~jbaron/rhel4/
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2006-0575.html