I'm preparing a migration to Zimbra. Currently I have Exim+Dovecot with local users on host domain1.com. The goal is to make it Zimbra with ldap authentication on mail.domain2.com (and domain1.com as an alias, so that users will be able to log in using both old and new urls).
The plan is:
1) install Zimbra on host mail.domain2.com
2) add virtual host domain1.com
3) import users from ldap, give them all a standard password
4) sync mail using imapsync (dovecot master user is a nice feature, wish Zimbra had that one)
5) shutdown host domain1.com
6) reset all paswords in Zimbra to blank
7) configure ldap authentication in Zimbra
8) point domain1.com dns A record to mail.domain2.com
Does it look good? Anything I missed?