On 2/20/2012 7:25 PM, Joseph Tam wrote:

Steve Campbell wrote:

...

The more I read about all of this, the more I'm thinking about moving to maildir format. My switchover this weekend is full of holes due to the way user's imap folders were laid out. Some had folders in their home directory and others might have folders in their /home/mail directory.

I had the same problem, and handled it more or less the same way as the later poster (Jim Lawson <jtl+dovecot@uvm.edu>) handled his site. I retained use of mbox format as well.

I planned the migration like this

- scan user home directories for mailboxes (especially "Trash",
"Drafts", "Sent", etc.) looking for "From " as the first 5 bytes.

This was piped into a script that Email'd users about the changes
that was going to happen, what they would expect to see, and a
FAQ on how to set up a mail client correctly.

Here, I'm not sure what should be done. The users with the secondary folders that are not in ~/mail can't seem to get the client configured.

- during the cutover,

    - mailboxes left on the home directory were moved to
    ~/mail, or renamed (e.g. "Sent" -> "00Sent" to avoid
    name collision for users that had a mixture of correct
    and blank prefixes.

I've tried this and modified the .mailboxlist, but I'm thinking Dovecot is ignoring this and I'm not sure what it's looking at to determine the imap folders.

    (I think I deleted "Trash", "Junk", etc. anyways).

    - Namespace aliasing was used so that prefixes "", "mail",
    "~/mail", and whatever darn fool settings my users used,
    would map to the same directory.

    - .subscription files were moved into the mail folder
    (don't have to edit prefixes since the aliasing
    will take care of that).

And when would these .subscription files be created? The first time the folders would be accessed, or when? This seems to be part of my fix that I'm getting lost on.

    - depending on what POP3 client you used (I used
    qpopper), you may need to configure

        pop3_reuse_xuidl = yes

    to avoid a massive re-downloading from POP3 clients
    after cutover.

    - the mail clients I control centrally (e.g. webmail,
    public server mail clients, etc). shouldn't need updating
    since they ought to have been set up properly in the first
    place.

- after cutover, a second notification was sent for users that
didn't move their mailboxes the first time around, and was it
done for them during migration.

And of course, test like crazy and watch the logs like a hawk.

Other gotcha's:

- your setup is fairly close to mine, so you may also run into
the problem of user having mailboxes with group ownership that
users are not part of (for example, group "mail" for INBOX set
by your LDA or personal mailboxes with groups the user is no
longer a member of) *and* with group permission not mode=0.

Sendmail sort of requires the "mail" group, does it not? I'll take a look and see if all users are part of this or not. A crazy solution would be in order here?

You'll have to treat these (set mode=0, or change the group to
something the user is part of), or the dovecot index creation
will fail and they won't be able to access their mailboxes.

I think my migration went pretty smoothly. Less than a handful of wazzup' Email problem reports.

Except for those users with the different folder locations, it seems that all is going pretty well. Maybe they're just not notifying me yet, though.

Joseph Tam <jtam.home@gmail.com>

Thanks steve