Our company have been using Zimbra for over a year. We are on version 4.5.4 RHEL 4 (32 bit) and have approximately 50GB of email across all users. We would like to move Zimbra to a new server running RHEL5 on 64 bit architecture. In the development environment we successfully moved all our maiboxes to the new server. First we performed a full backup on the production server and then loaded these backups onto a new 64bit RHEL5 machine. Furthermore, we were able to upgrade Zimbra to 4.5.7. Everything seems fine.
It is my understanding that Zimbra doesn't officially support a direct move from 32bit RHEL4 to 64bit RHEL5 architecture. Since we were able to do it in the development, is it safe to convert our official Zimbra email using this technique ? What are possible risks ?