This procedure is specifically used to move mailboxes from UNIX /var/mail format folders into a Sun Java System Messaging Server message store. However, if the messaging server from which you are migrating can convert the IMAP message stores to UNIX /var/mail format, then you can use the imsimport command to migrate messages to the Sun Java System Messaging Server. Consider the advantages and disadvantages before moving mailboxes using this method.
The advantage of moving mailboxes using the imsimport command is as follows:
System administrators have complete responsibility for moving mailboxes from the old system to the new system. Users do not have to do anything.
The disadvantages of moving mailboxes using the imsimport command are as follows:
This method takes longer to move mailboxes than the other non-IMAP methods.
Users access to mailboxes must be disabled while mailboxes are being moved.
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 if needed.
You can use Delegated Administrator to do this. Do not switch over to the new system yet.
Disable user access to both the new and old messaging store.
Set the mailUserStatus LDAP attribute to hold. User’s mail is sent to the hold queue and access to the mailbox over IMAP, POP, and HTTP is disallowed. MTA and Message Access Servers on the store server must comply with this requirement. This setting overrides any other mailDeliveryOption settings.
If the mail store from the existing mail server is not already in the /var/mail format, convert the mail store to /var/mail files.
Refer to the third-party mail server documentation.
Run the imsimport command.
imsimport -s /var/mail/joe -d INBOX -u joe
See the imsimport in Sun Java System Messaging Server 6.3 Administration Reference for details on the imsimport command.
Enable user access to the message store.
Set the mailUserStatus LDAP attribute to active.
Enable user access to the new messaging store.
Shut down the old system.