On Sun, Feb 20, 2005 at 11:25:37PM -0600, Alex Adriaanse wrote: > This morning was the first time my backup script took > a snapshot since upgrading to 2.6.10-ac12 (yesterday I had taken a few > snapshots myself for testing purposes, this seemed to work fine). a) Activating a snapshot requires a lot of memory;
b) If a snapshot can't get the memory it needs you have to back it out manually (using dmsetup - some combination of resume, remove & possibly reload) to avoid locking up the volume - what you have to do depends how far it got before it failed; c) You should be OK once a snapshot is active and its origin has successfully had a block written to it. Work is underway to address the various problems with snapshot activation - we think we understand them all - but until the fixes have worked their way through, unless you've enough memory in the machine it's best to avoid them. Suggestions: Only do one snapshot+backup at once; Make sure logging in as root and using dmsetup does not depend on access to anything in /var or /home (similar to the case of hard NFS mounts with the server down) so you can still log in; BTW Also never snapshot the root filesystem unless you've mounted it noatime or disabled hotplug etc. - e.g. the machine can lock up attempting to update the atime on /sbin/hotplug while writes to the filesystem are blocked Alasdair -- [EMAIL PROTECTED] - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
