Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
CentOS 5.5 x86_64 (2.6.18-194.32.1.el5), drbd 8.3.8-1. I am concerned about the usefulness and/or accuracy of the drbd verify operation. Running 'drbdadm verify' on a resource, I get these messages in the log: Feb 20 20:02:29 tiger kernel: block drbd11: Out of sync: start=622335312, size=8 (sectors) Feb 20 20:02:34 tiger kernel: block drbd11: Out of sync: start=623124784, size=8 (sectors) ... Feb 21 02:04:48 tiger kernel: block drbd11: Online verify done (total 25857 sec; paused 0 sec; 75504 K/sec) Feb 21 02:04:48 tiger kernel: block drbd11: Online verify found 6 4k block out of sync! Feb 21 02:04:48 tiger kernel: block drbd11: conn( VerifyS -> Connected ) Feb 21 02:04:48 tiger kernel: block drbd11: Writing the whole bitmap, due to failed kmalloc Feb 21 02:04:49 tiger kernel: block drbd11: 24 KB (6 bits) marked out-of-sync by on disk bit-map. Observations and problems: - It says "Online verify found 6 4k block out of sync" whereas there were actually 25 "Out of sync:" messages. - The verify was run after a re-sync of the whole device, so presumably there should be no positives, real or false, at all. - If I repeat the verify, it will show a different number of out of sync blocks at different places. Same for a further repeat, etc. Given this, and also that I have seen several other people report a similar situation, it appears impossible to use the verify operation in real life, and further it appears impossible to find out if a resource is really in sync. I would hope that the drbd developers and other knowledgeable folk would comment on this. Steve