Quoting Greg Woods <[EMAIL PROTECTED]>:
On Thu, 2008-10-23 at 10:48 -0600, Landon Cox wrote:b) apache, postgresql, mysql and some custom services are always running on both machines to reduce startup times on failoverYou might want to carefully consider the tradeoff here. Getting two-way database replication to work reliably can be a huge headache. I have no experience with postgresql, but I've never been able to make this work with mysql. I found it was just easier to use DRBD to replicate the database at the disk partition level, and put up with the startup time on failover. Even with a good-size database (that stores several days worth of e-mail for our 1200-employee organization), it's at most a few seconds for mysql startup. It was a small price to pay to avoid the headaches associated with database-level replication. Do you really have an application where you can't even afford a few seconds down time at failover? It is also unclear to me that you can bind an application to an interface like eth0:0 that doesn't even exist when the application is started (it is created by heartbeat at failover time). Thus it might not even be possible to have your apps running before failover and have them listening on the service address after failover. Has anyone actually tried this?
Greg: You're right about the binding issue - at least at first blush. You _can_ set up the IP address and bind it to the loopback address, then insert and remove the route as the heartbeat managed resource. It's kind of a pain, and it isn't obvious that it's actually faster - or at least much faster - unless MySQL is really slow to start up.
-- Alan _______________________________________________ Linux-HA mailing list [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
