Cyrus upgrade from 2.1.18 to 2.2.13 moved email messages

[Steinar Bang]

>>>>> Steinar Bang <sb at dod.no>:

>>>>> Sebastian Hagedorn <Hagedorn at uni-koeln.de>:
>> -- Steinar Bang <sb at dod.no> is rumored to have mumbled on 28. November
>> 2007 20:55:16 +0100 regarding Cyrus upgrade from 2.1.18 to 2.2.13
>> moved email messages:

>>> What previously was mail/s/user/sb/ is now mail/u/s/user/sb/

>> That means you are using fulldirhash. It's an option in /etc/imapd.conf.

> Ok.  Thanx for the info!

There is no fulldirhash setting in /etc/imapd.conf, but there is this
hashimapspool setting:

 # If enabled, the partitions will also be hashed, in addition to the hashing
 # done on configuration directories. This is recommended if one partition has a
 # very bushy mailbox tree.
 hashimapspool: true

Not sure what they mean with a very "bushy mailbox tree".  By "they" I
mean the debian package maintainers.

[snip!]
>>> And my restored mailbox.db probably points to the old structure...?
>>> So how to I create one that points to the new structure?

>> It might be easier to reverse the process. Disable the feature and run
>> rehash. No promises, though.

Here's the step in /usr/share/doc/cyrus-common-2.2/UPGRADE.Debian.gz
that probably caused it:
 7. Run the rehash program.

    $ /usr/lib/cyrus/upgrade/rehash basic

The document has running ctl_mboxlist as the next step to restore the
mailboxes database, from what looks to be the existing one (no dump done
previously in the document).

Was this step supposed to change the layout settings of the mailboxes?
If so, is this change documented somewhere?  Ie. the format of the
mailboxes plain text file and what it means, and what I should change?

I only have a handful of mailboxes, so it's fairly easy to do the
changes manually.