[Dovecot] converting from maildir to mdbox ?

[Jan-Frode Myklebust]

I´m considering moving from maildir to mdbox, but don´t quite see how
I should do the conversion with minimal downtime. Our userdb is ldap,
and the we use this setting to point to the users maildirectory:

user_attrs = mailMessageStore=mail=maildir:%$:INDEX=/indexes/%1u/%1.1u/%u,mailQuota=quota_rule=*:storage=%$

i.e. every user has a "mailMessageStore" attribute in LDAP that points
to his INBOX. Any ideas for how we can migrate user by user to mdbox?
Can we add a mailboxFormat attribute to LDAP, and somehow get that
used in the user_attrs lookup ? Ideally have it default to maildir if
not set, so that the current setup isn´t changed and only migrated
users are affected. Or should we be keeping the mailboxFormat as a
prefix in all mailMessageStore strings ?


  -jf