Hi, This isn't a direct RHCS related question so feel free to point me to a better list or respond off list, etc. I've been following this list mostly for the purposes of attempting to get my DRBD+GFS2+CMAN clustering working (so far unsuccessfully as it doesn't appear to fence). I don't think I've done any posting yet, just lurking. In the mean time while troubleshooting DRBD I've been running two geographically distant groups of web servers, replicating data to each other in several groups of local/remote csync2 "clusters". I guess it's not technically a clustering system at all but rather a file mirroring system similar to constantly rsync'ing files back and forth between each server pair. I've added some wrapper scripts to provide some locking and prevent it from running synchronously since it tends to fail when it does. Replication however still isn't a speedy process (hence my attempts to utilize DRBD/GFS to satisfy those above me) with a minimum max replication time of two minutes. Replication is cron'd to run on one server during odd minutes, on the other server on even minutes. We've got a 2xT1 on one end and a 10M line on the other. A 100MB file for example would take 3 minutes 13 seconds to transfer or so if both the local and remote connections were relatively idle and nearly maxes out a 2xT1 line. A 512mb file about ten minutes. I would suspect that other clustered disk replication technologies out there (although I haven't seen many methods to do this other than DRBD, rsync, and home brew solutions) would have similar replication times and be limited almost entirely by connection speed and traffic congestion. So how do you deal with replication delays in a web cluster where two browsers hitting different servers are supposed to both be able to download the same 50mb PDF but one server may not have that entire file yet. Phrases like "build scheduling into the CMS" tend to be like an old stick of dynamite around here. ___ Dan Brown danb@xxxxxx -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
