Migrating Zimbra7 from SLES to Ubuntu, then Upgrade to Zimbra8
We're trying to figure out the best way to go about this migration. We're currently running Zimbra 7.2.2_GA_2852.SLES11_64_20121204211855 SLES11_64 NETWORK on SLES 11sp2 on 4 HP servers (1 ldap, 2 MTA, 1 mailbox), and we're looking at moving to a 3 server virtualized (esxi) environment (1 proxy, 2 ldap/mta/mailbox) on Uubuntu.
Our first plan was to simply install the Zimbra 7 proxy on the first Ubuntu VM server (to hide what's coming from our users) into the existing Zimbra system, install the other 2 servers into the system (making for a 7 server system), then migrating the mailboxes to the new mailbox servers, setting one of the new servers as the ldap master, then removing the original 4 servers from the Zimbra system.
Once migrated, the plan was to upgrade the system to Zimbra 8.07.
While this seemed like a good plan to begin with, once we began serious planning, it's more complicated.
We want to use Ubuntu 12.04LTS, but the Zimbra 7 Ubuntu dist is for v10LTS. Is it possible to install Zimbra 7 on top of Ubuntu 12.04LTS? If not, would we need to install it on Ubuntu10LTS, then upgrade Ubuntu to 12LTS before upgrading the Zimbra to v8?
Due to backup issues (actually restoration issues. A total restore if the upgrade went really wrong would take about 40 hours) with our existing system, we'd rather not upgrade in place to Zimbra 8. Plus, since we're on SLES 11sp2, we could only upgrade to 8.03 (I think).
Any ideas on the best way to go about this would be very much appreciated!
Network Administrator - QC Holdings, Inc
Release 7.2.2_GA_2852.SLES11_64_20121204211855 SLES11_64 NETWORK edition.