On Wed, 2010-11-17 at 21:02 +0000, Colin Simpson wrote: > On a two node non-shared storage setup you can never fully guard against > the scenario of node A being shutdown, node B then being shutdown later. > Then node A being brought up and having no way of knowing that it has > the older data than B, if B is still down. I was under the impression that this was solved by adding in the quorum disk. Is that not correct? [...] > Three nodes just adds needless complexity from what you are saying. I thought that a third node could be acting as a "quorum server". If A can still reach that third node (C), then A and C have quorum. The same is true if one replaced A with B. If A and B retain contact with each other, but lose touch with C, quorum still exists. You're right, though, that this doesn't solve the scenario you described above. Solving that by adding a third node would involve having C somehow inform A and B which amongst them had been up most recently. A quorum disk would be simpler *if* the quorum disk solves this problem. Does it? How does this problem get solved in the DRBD world w/o an additional layer of clustering? Thanks... - Andrew -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
