Hi --
On 14.03.2012, at 15:09, Timo Sirainen wrote:
On Wed, 2012-03-14 at 01:25 -0400, Michescu Andrei wrote:
The problem comes when I start using the master-master model: emails starts getting duplicate with different ids.
I was testing this a bit, and I guess in your tests dsync was running during a mail delivery, which seems to make it duplicate mails sometimes. I'll probably fix this at some point (I've actually been thinking about a larger dsync redesign),
Good to hear ;-)
but anyway:
Even if dsync worked perfectly and didn't duplicate mails, it's not a great idea to do deliver mails randomly to both servers.
Sometimes croncobs are running on both servers at the same time producing locally delivered mails simultaneously, though. Ok, one can modify run times accordingly ...
Why do you run the crontab on all the servers? You can run a start-based system where only one ("main"-master) syncs all the other masters. And like this you avoid the time synch'ing of crontabs (especially if you don't always know how longer it will take for a dsync to finish).
Better to give one MX a higher priority so mails typically are delivered through it.
That's what I did. Now dsync/replicator is performing great, if the mail volume is rather low. I'm very satisfied, because this is the best performance ever. (Before I was running unison and dsync 2.0.)
But, whenever the high priority server will show delays during stress situations like huge mail loads, the low priority server will receive loads of mails as well. A dsync/replicator setup will then most probably produce duplicates (and multiples). That is a rather unrealistic scenario for my little severs, but others might have more difficulties.
This is another nice case to "motivate" Timo to look for solutions ;) I tried to push 2 ideas in the same direction earlier :P Especially that he confirmed that every single email has a unique GID (which should help prevent duplication/multiplication)...
And spammers don't care about mx priorities at all :-(
Actually, statistically speaking, spammers select the low priority ones.
Regards, Michael
Nice to hear that we are not the only ones out there to try to run something like this over dovecot :P
Thnx, Andrei