ejabberd - Comments for "Clustering support with MySQL?"

Why clustering with MySQL?

Jxn — Thu, 15 Jun 2006 20:49:59 +0000

Erlang and Mnesia is constructed ground up for clustering. And prob. does that better than MySQL or any other SQL database server.

I can understand taking out some stuff for some stuff that doesn't change that much, like users and vCards. Other information I would take out with XMPP protocol.
Or if you would likt total access, write Erlang code to take that information out for you. Your code could be running on another machine and connect through Erlang to your ejabber-node (for security and load sharing).

For backup purposes, you can do that from your ejabberd. If you want to have the backup on another node, connect one ejabberd-node on another machin and take the backup from that node (except from mod_mud, that can't be clustered now).

You prob. need to give some more information of your needs, so some one could give a propper/right/good solution for your problem. Hopefull a better one than what you try to do.

Anyway, good luck with ejabberd and what you like to doo with it.

Re: Clustering support with MySQL?

sander — Wed, 17 May 2006 21:22:29 +0000

marius wrote:

The statement, "Which tables to replicate is very dependant on your needs" in the documentation doesn't really help much to a newbie like me. ;)

I agree that that section in the guide needs to be improved.

Re: Clustering support with MySQL?

marius — Wed, 17 May 2006 20:49:44 +0000

sander wrote:

marius wrote:

The documentation seems to indicate that clustering requires Mnesia. Is there a way we can make clustering work with MySQL (db on another server)? I'd think having a centralized database is more ideal when you want to cluster jabber nodes....

I'm not sure if Mnesia is really needed for clustering (though, there are always tables stored in Mnesia). But remember that Mnesia is a clusterable database, which means that several database tables on each server are the same (not all, because it would be a waste of resources to duplicate e.g. the presence table on all nodes).

Right now we're using MySQL to store as much as possible: users, vcard, offline, etc. I'm assuming everything else is stored in Mnesia and I'm not sure if any of them need to be replicated. The statement, "Which tables to replicate is very dependant on your needs" in the documentation doesn't really help much to a newbie like me. ;)

Re: Clustering support with MySQL?

sander — Wed, 17 May 2006 09:17:42 +0000

marius wrote: