Multiple partitions may be used for various reasons, such as to distribute load between different storage pools or technologies. Please consult Mail Spool Partitions for more details and use cases.

To define additional mail spools, add more partition-name entries to imapd.conf(5) as needed. For example, let’s imagine we want to migrate users to new partitions split by first character of the user’s last name, and add a partition for shared mailboxes (see Shared Namespaces):

  • Sample:

    defaultpartition: main
    partition-main: /var/spool/imap
    partition-am: /var/spool/imap-am
    partition-nz: /var/spool/imap-nz
    partition-shared: /var/spool/imap-shared