This procedure can be used anytime messages need to be migrated from one messaging server to a different messaging server. Consider the advantages and disadvantages before moving mailboxes using this method.
The advantages of moving mailboxes using IMAP clients are as follows:
This method can be used to migrate from a non-Sun Messaging Server to the Sun Java System Messaging Server. It can also be used to move mailboxes from one physical server to a different physical server.
After system administrators set up the new mail server or message store, responsibility for moving mailboxes to the new system is left to users.
The process for moving mailboxes is relatively simple.
User access to mailboxes does not have to be disabled.
The disadvantages of moving mailboxes using IMAP clients are as follows:
Requires that both the old and new systems be simultaneously running and accessible to users.
Cumulatively, this method takes longer to move mailboxes than other methods.
Responsibility for moving mailboxes to the new system is left to users.
The size of the new message store will be significantly larger than the old message store until the re-linking operation is performed.
Install and configure the new Messaging Server.
Set local.store.relinker.enabled to yes.
This will reduce the message store size on the new system caused by duplicate storage of identical messages. See 20.11.7 Reducing Message Store Size Due to Duplicate Storage of Identical Messages for more information.
Provision users on the new Messaging Server.
You can use Delegated Administrator to do this. As soon as users are provisioned on the new system, newly arriving mail will be delivered to the new INBOX.
Have users configure their mail client to view both new and old Messaging Server mailboxes.
This may involve setting up a new email account on the client. See mail client documentation for details.
Instruct users to drag folders from their old Messaging Server to their new Messaging Server.
Verify with users that all mailboxes are migrated to the new system, then shut down the user account on the old system.