On Thu, Nov 15, 2012 at 03:12:09PM +0100, Martin Emrich wrote: > Hi! > > > Apologies if this is a dumb comment, but isn't master-slave, by definition, only in one direction? If you could write on all nodes, it would be multi-master, yes? > ? > I would say it depends on the definition. Master-slave is surely asymmetrical, as the replication can only be triggered by the master. But the data flow could be bidirectional anyways... It's unidirectional: writes go to master, writes replicate from master to slave. I believe it's basically rsync on steroids (with some help from xattrs to track changed files) Any multi-master replication suffers from exactly the same split-brain scenarios as you described earlier. In glusterfs, geo-replication is what you should use for WAN-separated sites. Replicated volumes are for LAN scenarios where partitioning (and hence split-brain) should not be expected to occur. If this doesn't meet your requirements then glusterfs is not the right tool for you. Regards, Brian.
