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Re: Mirror Mode, MMR and replicas
--On Wednesday, March 18, 2009 10:18 PM +0100 Rein Tollevik
Quanah Gibson-Mount wrote:
--On Wednesday, March 18, 2009 3:01 AM -0700 Howard Chu <email@example.com>
I'll start with replication under MMR.
As I understand it, the replicas can only point at a single master.
Last I checked, the provider parameter in the syncrepl configuration
block was single valued. Which means either it gets pointed at a load
balancer, or it only talks to a single master. If that master goes
down, it no longer talks to anything without reconfiguration.
Each syncrepl engine (configuration block) can only refer to a single
master, but you may configure many engines within the same database, each
with its own master. If one master goes down the engine using that
master will obviously not receive any updates until its master is up
again, but the other will continue to receive updates from their master.
Ok, this was the point I didn't realize -- That syncrepl on a replica will
correctly handle looking at two masters providing the same changes to it.
Principal Software Engineer
Zimbra :: the leader in open source messaging and collaboration