Hi all:<br><br> Is there a way to check the data integrity on both node? I've encounter an confusing problem. <br><br>We have two drbd devices, 20Gb one for application, and 300Gb one for oracle database(oracle was installed in a different location, which were not replicated), csums-alg & verify-alg were configured to crc32c, bandwidth was 100M.<br>
<br> I try to upgrade our app & database on secondary(node2) , by disconnect and promote 2 drbd devices to primary and then perform the upgrade, it was fine. Then I try to roll back the seondary the original version, by drbdadm -- --discard-my-data connect drbdX. After drbd sync, oracle was unable to startup, it reports data corruption. So I issue drbdadm verify, but it doesn't report anything, everything seems good.<br>
<br>I disconnect drbds and then mount them on both side, md5sum all files on the disk. I diff the output from both side and found that serval database file's md5 value wasn't identical. Then I connect drbds and found that it begin to sync about 30Gb's data. I didn't the device read only, but have all applications stopped.<br>
<br><br>BTW, In earier, I've try to recovery the underlying lvm devices from snapshot, but get IO error, so I just canceled and resync it. Does it matter? Since I've get rid of drbd there.<br>