On Fri, Sep 15, 2006 at 06:35:32AM +0200, Vidar Tyldum Hansen wrote: > Paul F: > > Alain Fauconnet wrote: > > > >>> d) Now heres maybe a tough one... has anyone played with trying to > >>> build a TSL 3.x high availablity mail server? I wander what options > >>> there might be? > >>> > >> I use the poor man's cluster: rsync in a shell script invoked by > >> crontab, a cold standby box and either dynamic DNS or a redirector > >> front-end. Rsync is quite workable with Maildir mailboxes, even > >> many/big. This is for POP/IMAP/outgoing SMTP. > >> It's admittedly not perfect, mail received since the last rsync is > >> offline after you fallback to the standby server, and after you switch > >> back to the master one, you need to resync by hand. It's the cheap > >> approach. > >> > >> For incoming SMTP backup MX works just fine. > > Thanks Alain a couple more questions: > > > > How frequently do you run Rsync? > > Can't answer for Alain, but I can give my piece of advice. > The answer depends on your volume of email. I have 250 users and if I > were to do it like Alain here suggests I could rsync every hour, or even > every half hour. It's quick and efficient, and you can offload your > network (if needed) either by having a seperate network for backups or > simply a crossover cable between the backup and the main.
I run it every hour too, on a server with 3500+ users (quota per user: 100Mb). It goes over a separate Gig LAN. Induced load is hardly noticeable (I don't use compression in rsync). > > > What do you mean by resync by hand? Do you mean simply copy the files back? > > Once the main server is back online you need to copy over the mail from > the backup again. This must be done manually and is hard to automate, at > least not smart to automate ;) Well actually you can rsync the other way around. I have a script for this but I run it by hand after switching back to the main server. > > > Finally, what if any is the recommended way to migrate the client from POP3 > > to IMAP? Simply select all the items in (Outlook?) and copy them to the new > > new folder containing IMAP? > > Yes. Since they have used POP the email is stored locally on the client. Well not necessarily. Some users may choose to leave mail on server. In that case you have both and you can use one of the mailbox-to-maildir scripts to do the job. > If you have their PST-files on a share you might find some parser that > can do this, but simply drag and drop works on Outlook (but not on > express, there you have to create the folders first and then move > messages folder by folder). > Use the opportunity to make the users clean out their mailbox so that > your storage space isn't eaten away with old junk. In my experience, most users don't even bother. They keep the old mail in their local mailboxes and start getting the new mail from IMAP. That's one mail archiving pass for free :-) Greets, _Alain_ _______________________________________________ tsl-discuss mailing list [email protected] http://lists.trustix.org/mailman/listinfo/tsl-discuss
