On 2019-03-20 1:46 p.m., Valentin Vidic wrote: > On Wed, Mar 20, 2019 at 01:34:52PM -0400, Digimer wrote: >> Depending on your fail-over tolerances, I might add NFS to the mix and >> have the NFS server run on one node or the other, exporting your ext4 FS >> that sits on DRBD in single-primary mode. >> >> The failover (if the NFS host died) would look like this; >> >> 1. Lost node is fenced. >> 2. DRBD is promoted from Secondary to Primary >> 3. ext4 FS is mounted. >> 4. Virtual IP (used for NFS) is brought up. >> 5. NFS starts >> >> Startup and graceful migration would be the same, minus the fence. > > Would it be possible for DRBD to go into SplitBrain if the lost node > manages to write something to local DRBD disk before it gets fenced?
Not when DRBD is configured correctly. You sent 'fencing resource-and-stonith;' and set the appropriate fence handler. This tells DRBD to not proceed with a write while a node is in an unknown state (which happens when the node stops responding and is cleared on successful fence). -- Digimer Papers and Projects: https://alteeve.com/w/ "I am, somehow, less interested in the weight and convolutions of Einstein’s brain than in the near certainty that people of equal talent have lived and died in cotton fields and sweatshops." - Stephen Jay Gould _______________________________________________ Manage your subscription: https://lists.clusterlabs.org/mailman/listinfo/users ClusterLabs home: https://www.clusterlabs.org/