On Mon, 2006-08-21 at 14:13 -0400, Sutterfield, Geary L. wrote: > Hello all, > > Does anyone have any information or experience about using GFS and the > Cluster Suite and JBoss Clustering on the same cluster? I've been > looking for a couple of days, but I can't seem to find any information > on that configuration. Our goal is to create a J2EE cluster with a > shared, global filesystem. GFS seemed like a logical choice. > > I'm speculating that if Cluster Suite was only used for GFS, and not > for any other services, then it might work okay with JBoss Clustering. > Cluster Suite would handle the GFS clustering, and JBoss Clustering the > J2EE app server clustering. But I also wonder about conflicts or > incompatibilities. And I especially wonder how fencing would impact > JBoss. Has anyone tried this configuration, or heard of anyone who has? I have not tried it, but here are some of the 'gotchas': (a) Disagreements in the JBoss cluster view vs. the GFS cluster view. GFS cluster view should always win in the end, because it has fencing. So, the GFS/RHCS cluster should be configured to converge on membership changes before JBoss (whether that means increase deadnode_timeout, or tweaking JBoss is up to you). (b) Cluster quorum. I don't know much about JBoss clustering (yet), but remember that cluster suite / GFS need a majority of votes (normally, there's a 1:1 correlation between nodes and votes) available in order to form a quorum. Without a quorum, access to GFS will be halted. (c) Fencing. You will probably need to use power-based fencing, because storage/SAN level fencing will not drop a node out of the JBoss cluster by itself. Since I don't currently know much about JBoss clustering generally, I also don't know the specific implications of trying to run JBoss on a given node after the GFS volumes have been cut off from that node. I *assume* that JBoss would take that node out of the JBoss cluster. > If there any problems, I suppose they will be worked out eventually, > since Red Hat has acquired JBoss. But we don't want to waste a lot of > time going down a path with known problems. Any thoughts or feedback > would be appreciated. -- Lon -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
