On Wed, Apr 21, 2010 at 1:09 PM, Robert Grignon <rgrig...@fleetone.com> wrote: > > I am investigating High Availability solutions for my front end servers.
Always good to hear. > I got into a discussion regarding "replicated local databases" versus " > a single fiber connected shared database" on an EMC. I will guess that you mean MySQL Master/Slave replication. > Is anyone running a shared database on a SAN? Care to comment on your > findings... I am running MySQL on shared SAN LUN, but not for Asterisk. Since SANs are expensive, I have been using DRBD/GFS2/MySQL for most of my low budget HA Asterisk installations. Some things to think about: 1. If you are using MySQL, then only one server can have the database open at a time. You will have some lag/downtime when the active server fails and the secondary has to take over. You are going to have this anyway even with a Master/Master replication as the IP has to shift. Same with Master/Slave plus you add time for a script to promote the Slave. 2. Don't even think about using MyISAM... InnoDB *only*. MyISAM doesn't check improperly closed tables until they are accessed which can cause some major lag. Not to mention no transaction support. You won't have another copy if things get corrupted (besides all of your backups of course) 3. While nice SANs are redundant, you are still adding another dependency to the system (a few if you are using FC switches). Make sure everything has multiple paths, and don't forget to configure fencing for the nodes. 4. If you have PRI/Analog lines to the server, then it becomes more of a headache. Use dependable redundant SIP gateways, or have some action plan in place. 5. Test, test, test then test some more. Break it in the lab and know how to fix it. Setup is easy, repair can be a pain. (You also want to know it will actually work =) That's my quick $0.02, and there is a lot more to think about too. Overall, if designed right I think it is a good option. Just depends on your level of comfort with the technologies, and the risk/benefit that goes along with it. -Jonathan -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users