[ovirt-users] Re: VM disk corruption with LSM on Gluster

+Krutika Dhananjay and gluster ml On Tue, Mar 26, 2019 at 6:16 PM Sander Hoentjen <sander(a)hoentjen.eu&gt; wrote: > Hello, > > tl;dr We have disk corruption when doing live storage migration on oVirt > 4.2 with gluster 3.12.15. Any idea why? > > We have a 3-node oVirt cluster that is both compute and gluster-storage. > The manager runs on separate hardware. We are running out of space on > this volume, so we added another Gluster volume that is bigger, put a > storage domain on it and then we migrated VM's to it with LSM. After > some time, we noticed that (some of) the migrated VM's had corrupted > filesystems. After moving everything back with export-import to the old > domain where possible, and recovering from backups where needed we set > off to investigate this issue. > > We are now at the point where we can reproduce this issue within a day. > What we have found so far: > 1) The corruption occurs at the very end of the replication step, most > probably between START and FINISH of diskReplicateFinish, before the > START merge step > 2) In the corrupted VM, at some place where data should be, this data is > replaced by zero's. This can be file-contents or a directory-structure > or whatever. > 3) The source gluster volume has different settings then the destination > (Mostly because the defaults were different at creation time): > > Setting old(src) new(dst) > cluster.op-version 30800 30800 (the same) > cluster.max-op-version 31202 31202 (the same) > cluster.metadata-self-heal off on > cluster.data-self-heal off on > cluster.entry-self-heal off on > performance.low-prio-threads 16 32 > performance.strict-o-direct off on > network.ping-timeout 42 30 > network.remote-dio enable off > transport.address-family - inet > performance.stat-prefetch off on > features.shard-block-size 512MB 64MB > cluster.shd-max-threads 1 8 > cluster.shd-wait-qlength 1024 10000 > cluster.locking-scheme full granular > cluster.granular-entry-heal no enable > > 4) To test, we migrate some VM's back and forth. The corruption does not > occur every time. To this point it only occurs from old to new, but we > don't have enough data-points to be sure about that. > > Anybody an idea what is causing the corruption? Is this the best list to > ask, or should I ask on a Gluster list? I am not sure if this is oVirt > specific or Gluster specific though. Do you have logs from old and new gluster volumes? Any errors in the new volume's fuse mount logs?