Right now there's no cross LDAP instance zmmailboxmove, and you don't have any backup feature to use yet, so some ideas (minus share permissions):
Imapsync is just mail so you'd have to export other stuff using additional methods.
User Migration - Zimbra :: Wiki
ZimbraMigrate is handy and incorporates Imapsync + REST for contacts, calendars, and filters in one tool:
SourceForge.net: ZCS Tools
Or grab .eml & .metadata-
Export:
zmmailbox -z -m
user@domain.com getRestURL "//?fmt=tgz" > /tmp/user.tgz
Import:
zmmailbox -z -m
user@domain.com postRestURL "//?fmt=tgz&resolve=reset" /tmp/user.tgz
(Transfer them via rsync etc.)
The resolve= parameter has several options:
-"skip" ignores duplicates of old items (the default resolution).
-"modify" changes old items.
-"reset" will delete the old subfolder (or entire mailbox if /).
-"replace" will delete and re-enthem. (Reset will be a bit faster on an empty destination mailbox because it skips most dup checks.)
Don't remember when we added .tgz, works reliably fresh in 5.0.9 (with some additional duplication fixes in 5.0.10) - but going back far into the past there's the .zip formatter:
http:// server.domain.com/user/~/?fmt=zip&query=is:anywhere
(might prove interesting on 10G mailboxes - I haven't tried)
You have so many methods for putting messages back into Zimbra; CURL/zmmailbox addMessge/zmlmtpinject etc:
Recover data from store folders Moving Folders between users
Zimlets that use this idea - more for self backups (not restore)
Mail backup options for end users? (.eml)
zimlet to save email in a txt file (.txt or html)
RFE's:
Bug 19630 - Migration Tool zimbra to zimbra Bug 29573 - Enhance 'zmmailboxmove' to move mailboxes between different ZCS version Bug 30163 - zimbra-zimbra migration via tar formatter