Stephen Beynon [stephen@xxxxxxxxxxxxxxxxxxxxxxxx] wrote: > This is probably a stupid question, in which case I apologise in advance. > > I am looking to set up a number of machines with internal disks mirrored onto > an iscsi server. I aim to provide resiliance against disk failures, and the > iscsi server will be a handy single point to backup. > > I set up the following test mirror. > > # dmsetup status mirror > 0 16777216 mirror 2 254:8 8:16 32768/32768 0 1 core > # dmsetup table mirror > 0 16777216 mirror core 1 512 2 254:8 0 8:16 0 > > As a test I shutdown the iscsi server and continued writes to the mirror > device. As expected syslog recorded i/o errors on the iscsi lun, but writes > to the mirror continued. After waiting a few minutes I expected to see that > parts of the mirror were out of sync, however dmsetup status gave exactly the > same results as above. > > When I restarted the iscsi server blocks started to be written to the iscsi > server again, but the changes that happened during the iscsi server down time > were never replicated. Clearly this left the mirror in an inconsistent state > with the only indication of problems being in syslog. > > Is there any way I can configure dm-mirror to either mark the blocks as out of > sync when a write fails, and re-try the write later ? > > I am currently running Ubuntu gutsy on the client machines, so it does not > have dmeventd, but from reading the docs it it not clear that dmeventd would > help. What kernel version? -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
