Automatic purging of old email in all mailboxes

[Scott W. Sander]

I used this guide as the starting point for this postfix + Dovecot server:
http://www.binarytides.com/install-postfix-dovecot-debian/.

My /etc/dovecot/dovecot-users passwd-file only has username:password (as
mentioned in that article) and my userdb driver is static as laid out in
the article as well.  Therefore I do not have uid's.

As far as changing the userdb driver from static to passwd-file, I'm not
sure what the consequence of that would be for my existing mailboxes or my
Dovecot implementation in general.  Everything I needed thus far is
working, I just want to add clearing out old email automatically.


On Mon, Aug 29, 2016 at 4:13 PM Joseph Tam <jtam.home at gmail.com> wrote:

> "Scott W. Sander" <scottwsx96 at gmail.com> writes:
>
> > A few of the mailboxes in Dovecot receive hundreds of emails per day.
> I'd
> > like to automatically remove all emails in all mailboxes and mailbox
> > folders that were received more than 90 days prior to the received date.
> > As I'm a novice Dovecot administrator, I'm not exactly sure what the best
> > way to accomplish this is, but I've started looking at the "doveadm
> > expunge" command.  I figure I could create a cron job that calls this
> > command with the -A switch and that has a search query that finds all
> > emails older than 90 days.
>
> That more of less what I do.
>
>         doveadm expunge -A mailbox INBOX savedbefore 7d
>
> > Error: User listing returned failure
> > doveadm: Error: Failed to iterate through some users
>
> I think this may be avoided (or made into warnings) if you bracket all
> user UID ranges with
>
>         first_valid_uid = {first user uid}
>         last_valid_uid = {last user uid}
>
> Sean Greenslade <sean at seangreenslade.com> then writes:
>
> > Since you're using maildirs as the storage backend, it might be easier
> > to just write a small script in the language of your preference (bash,
> > python, perl, etc.) that walks the directory tree and deletes files
> > based on their mtime.
>
> The downside is that the Dovecot caches will be out of date.  Perhaps
> follow this up with a "doveadm index ..." operation.
>
> Joseph Tam <jtam.home at gmail.com>
>