Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
2009/3/27 Trinh, Hung <HTrinh at crossbeamsys.com> > Hello list, > > > > I’m running DRBD 8.2.5 on a couple of 64bit SMP PCs with CentOs 5.1. > > The PCs have one DRBD partition on /dev/sda3 and was completely synced. > > PC1 is Primary and PC2 is Secondary. > > After they were synced, I brought down the drbd device on PC2. > > > > On PC2 (secondary node): > > I ran fsck and mounted the /dev/sda3 to make sure the files look good. > > I changed the content of 1 file, umount the /dev/sda3 and brought the drbd > device up. > > > > > > The /proc/drbd on both PCs showed both nodes’s ds are up-to-date. > > I then brought down drbd on PC2 (secondary node), did fsck on /dev/sda3 and > mounted > > The file I modified did not get updated to match with the Primary node, > PC1. > > > > My questions: > > 1. Is this a correct behavior? > > Yes, it is. This is how DRBD is implemented - it is a kernel module that acts as a block-device driver. If you omit it when modifying the data, it has no way to recognise the modifications and propagate them. > 2. If so, how can I fix it without going through a full sync? > DRBD 8.2.7+ implement verify algorithm - compare device blocks using hash algorithms. It executes the out-of-date handler if it finds blocks that "look" differently between nodes. After that you can just reconnect secondary device, resync should start automatically. > 3. If so, is there a way to vadilate the integrity of DRBD devices? > > 4. If not, is this a bug? or I did something wrong? > You should not modify backing device directly, you should never modify backing device on secondary node. I'm not sure if verify algorithm can fix 100% of manually created inconsistencies. Regards. > > > > > Thanks for any help. > > > > - Hung > > > > _______________________________________________ > drbd-user mailing list > drbd-user at lists.linbit.com > http://lists.linbit.com/mailman/listinfo/drbd-user > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20090327/57b599fb/attachment.htm>