I've asked the DBA to review to see if this would be feasible and I've received the following response, he is speaking based on mysql he is not familiar with dbmail architecture, so I'm asking whether this is true.
"multi-master would be very difficult to be supported on mail servers as MySQL is running on Innodb engine and it would have problem with foreign key constraints as it supports row level locking so there might be conflicts of the primary key" Thank you. ----- Original Message ---- From: tabris <[email protected]> To: [email protected] Cc: DBMail mailinglist <[email protected]> Sent: Tue, May 18, 2010 7:49:54 PM Subject: Re: [Dbmail] dbmail and multimaster mysql replication N Sj wrote: > I've read through the archives and noticed that multimaster replication is > really discouraged to be used with dbmail, but I'd still like to see if I can > figure out a way to use my second mysql server to take some load off the > master server. Please find the scenario below where all the pop/imap clients > and SMTP from internet will be pointing to mysql-server1 and all the webmail > clients to mysql-server2. Both mysql-server1 and mysql-server2 are configured > with multimaster replication. > > Is it possible to do something like this or will it completely break dbmail. > > pop/imap ---->mysql-server1 > webmail ---->mysql-server2 > > From my experience, it's mostly safe as long as you NEVER have the same userid talking to both servers at the same time. And occasionally there will be a problem from one of the dbmail_headername or dbmail_headervalue tables. If you do have a user connecting to both servers at the same time (or at a time when one side is disconnected from the other's replication) you can end up with desyncs from the dbmail_folder table. And just to point out that it is possible, even if not recommended, I had a master<->master replication setup across the Atlantic Ocean (Paris, France <-> Santa Clara CA US) that worked, including having message insertion from both sides. I had more trouble from user IMAP actions than message-insertion (b/c the dbmail_headervalue and dbmail_headername tables are inconsequential). And this setup ran for 2 years w/ only one major mishap and a few minor ones (and probably a lot of dbmail_headername/dbmail_headervalue collisions). The major mishap was b/c some brightboi decided to reboot the server from the console w/o asking me first. _______________________________________________ DBmail mailing list [email protected] http://mailman.fastxs.nl/cgi-bin/mailman/listinfo/dbmail
