Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Hi all I am trying to find out what would happen in the following situation: 1. GFS writes to its GNBD device. GNBD client node writes to GNBD server node. GNBD server writes to DRBD-primary. DRBD begins to write to itself and to DRBD-secondary. Before DRBD completes the write to DRBD-secondary (thus, before it returns since writes are synchronous) the DRBD-primary node looses power. The GNBD server dies with the power loss. GNBD client node drops connection to the GNBD server. 2. Heartbeat notices the death of DRBD-primary, switches the DRBD- secondary to DRBD-primary, re-exports /dev/drbd0 via GNBD, and re-creates the virtual IP which the GNBD client was connecting to. 3. The GNBD client writing on behalf of GFS reconnects. Now, what happens to the write originally going to the DRBD volume? Will the GNBD-client retry the write? Are there situations where the write could be dropped all together? This has been taken from the post to the redhat-cluster list, but there was no answer: http://www.redhat.com/archives/linux-cluster/2007-March/ msg00131.html If anyone has some info, I would appreciate it. Regards Chris