Re: [Dovecot] Best way to migrate from Qpopper to Dovecot
Hi List,
what do you think is the best way to migrate (to a new maschine) round about 30000 mboxes (Qpopper) with an amount of 43Gigs data, to maildir format (Dovecot). I think there are two ways:
- stop services (smtp and pop3) on the old maschine
- copy the mboxes to the new maschine
- run a conversion script (for excample: "Perfect_maildir" http://perfectmaildir.home-dn.net/)
- start the services on the new maschine (smtp and Dovecot)
- tell the users to use the new server (from the day X) with the new feature (imap)
- stop the smtp on the old maschine on day X
- leave the old maschine active for a month or so (let users get their "old" mail)
With the first alternative we have a high downtime, because of copying the mboxes and converting the stuff.
What do you think?
Hello Torsten,
We switched our 3500+ users from Qpopper to Dovecot last week-end. We had around 27Gb of data to migrate. We had a maintenance window in which we could stop the POP services, so it was quite easy to do. Even if we changed hardware, we kept the old name and IP so that we had no DNS changes to do. Clean and simple.
Here's how we've done things on FreeBSD 6.2-RELEASE-p2
-- Shutdown qpopper POP services on the old machine. -- Create a tar and transfered it to the new machine. Acutally, this was a single step in which we used a pipe to send that tar STDOUT into ssh's STDIN. -- Import /etc/master.passwd and /etc/group from the old system into the new machine. -- Run a simple shell script to change from mbox format to Maildir using mb2md and set permissions. -- Exchange FQDN and IP between to old machine and the new one in order to prevent any DNS changes. -- Start Dovecot and your MTA on the new machine.
Concerning your desire to move your user's Maildir into /var/mail/first_letter_of_username/username. It should be trivial to do using a simple /bin/sh script.
Have fun !
David
David Robillard UNIX systems administrator & Oracle DBA CISSP, RHCE & Sun Certified Security Administrator Montreal: +1 514 966 0122
Hi David,
we did nearly the same procedure the last time we switched from an old Qpopper maschine to a new Qpopper maschine. The last time we had not so much users (maybe 16000), not so much data (round about 20Gigs) and there was no need of conversion. This time we have new DNS-Names, new environment (Dovecot) and so on.
So David, may I ask you how long did it take to convert the data?
Thanks Torsten
David Robillard schrieb:
Hello Torsten,
We switched our 3500+ users from Qpopper to Dovecot last week-end. We had around 27Gb of data to migrate. We had a maintenance window in which we could stop the POP services, so it was quite easy to do. Even if we changed hardware, we kept the old name and IP so that we had no DNS changes to do. Clean and simple.
Here's how we've done things on FreeBSD 6.2-RELEASE-p2
-- Shutdown qpopper POP services on the old machine. -- Create a tar and transfered it to the new machine. Acutally, this was a single step in which we used a pipe to send that tar STDOUT into ssh's STDIN. -- Import /etc/master.passwd and /etc/group from the old system into the new machine. -- Run a simple shell script to change from mbox format to Maildir using mb2md and set permissions. -- Exchange FQDN and IP between to old machine and the new one in order to prevent any DNS changes. -- Start Dovecot and your MTA on the new machine.
Concerning your desire to move your user's Maildir into /var/mail/first_letter_of_username/username. It should be trivial to do using a simple /bin/sh script.
Have fun !
David
participants (2)
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David Robillard
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Torsten