On Thu, 2005-05-05 at 18:49 -0400, Dan B. Phung wrote: > From my understanding, > the quorum/voting procedure is to prevent split-brain scenarios where two > nodes coming up for the first time might try to form two separate clusters > of the same name, which will cause data corruption. How would I prevent > that, while still allowing any one node, even by itself, to access the > storage media. It's not to prevent two nodes: it's to prevent "less than a majority" of the nodes (votes really) from forming their own cluster. What you're trying to do is exactly what the algorithm is designed to prevent :) Consider a case where any one node can become quorate (by itself) in an N-node cluster. If you unplug the network cables on each node and start up the cluster software on all N nodes, you'll end up with an N-way split brain! I think that is probably not a good thing. You can do it manually by adjusting cman_tool's expected votes down to a small number while doing a one-node boot, but please ensure the rest of the cluster is down before doing so. > Another use of the quorum is for distributed disks in the case of a node > failure the I/O to that disk is fenced. Is that correct? Yes. -- Lon -- Linux-cluster@xxxxxxxxxx http://www.redhat.com/mailman/listinfo/linux-cluster
