Hi there,
We're using Dovecot version 1.0.7 and Postfix, and since upgrading our
Linux box we're getting this in the maillog:
Nov 8 07:49:11 server1 postfix/local[27901]: 04B8E7081DA:
to=<x...@xyz.com>, orig_to=<a...@abc.com>, relay=local, delay=19,
delays=0.07/0/0/19, dsn=4.2.0, status=deferred (cannot update mailbox
/var/spool/mail/abc for user abc. unable to lock for exclusive access:
Resource temporarily unavailable)
Postfix is currently set to:
mailbox_delivery_lock = fcntl, dotlock
Dovecot has this:
mbox_read_locks = fcntl
mbox_write_locks = fcntl dotlock
I've scoured the web and tried all kinds of different locking mechanisms
and combinations to no avail. The mail is eventually delivered but on a
busy day this can take several hours.
In the evening it generally doesn't happen, which leads me to believe it
occurs during the day when people have their mail clients open.
However, this particular issue doesn't affect every user that has their
mail client open, only some!
We currently have the mailboxes in mbox format - yes I know we should
upgrade to maildir which we will eventually, however we've been using
mbox for the last 10 years and this has only become an issue since
upgrading.
What I have discovered this morning is a Dovecot connection that is open
for 6 minutes before disconnection. During this 6 minutes the above
problem occurs (new mail cannot get an exclusive lock). The same user
will have connected and disconnected several times before and after,
with a connection taking no more than a few seconds. But it seems
sometimes the connection is taking longer than it should and I suspect
the problem lies here.
Please can anyone help!
Thank you,
G
