I have Dovecot 1.0 in trial use by the IT staff, and have some locking
questions
Background, the mail server runs procmail, sendmail and NFS exports the
user homedir and mailbox to a) a login shell host and b) a mailing list
services host. It runs UWIMAP on the usual ports and dovecot on a
arbitrary port number. Because of concern with NFS and file access
contention. I have the following dovecot.conf file access parms set:
a) mbox_dirty_syncs = no
b) mbox_lazy_writes = no
1) I am seeing these errmsgs. Are they anything I should be concerned
about, or are they just the inevitable result of lock contention for
mailboxes and folders by procmail, imap/dovecot and NFS?
In syslog, I am seeing this:
Apr 23 18:46:34 mercury mail:err|error dovecot: IMAP(sdean):
stat(/var/spool/mail/sdean.lock) failed: No such file or directory
Apr 23 18:46:34 mercury mail:err|error dovecot: IMAP(sdean):
file_lock_dotlock() failed with mbox file /var/spool/mail/sdean: No such file
or directory
While in maillog:
Apr 23 18:46:34 mercury mail:err|error dovecot: IMAP(sdean):
stat(/var/spool/mail/sdean.lock) failed: No such file or directory
Apr 23 18:46:34 mercury mail:err|error dovecot: IMAP(sdean):
file_lock_dotlock() failed with mbox file /var/spool/mail/sdean: No such file
or directory
2) I earlier asked, but don't think I got an answer to this question:
Everybody wants to lock differently
1) procmail (delivering for sendmail), which seems to want to use
dotlocking, fcntl and lockf locking; for whatever reasons, the compile
time tests seem to disallow flock.
2) UWIMAP which according to wiki.dovecot.org/Migration/UW uses:
mbox_read_locks = flock
mbox_write_locks = dotlock flock
3) I want to run dovecot in the same environment as I switch over, for
which the locking strategy is supposed to be (according to
http://wiki.dovecot.org/MboxLocking)
mbox_read_locks = fcntl
mbox_write_locks = dotlock fcntl
Since that same page in the wiki says. "*It's important that all
software that's reading or writing to mboxes use the same locking
settings.",* I had recompiled procmail so it only usedotlocking and
fcntl (thus removing lockf in addition to the disallowed flock)...but
now I bumped into the Migration/UW page and there looks to be a conflict.
I want to be able to run dovecot (for testing) and UWIMAP (for all
users/production) at the same time (but never at the same time with
the same mailbox), but UWIMAP is doc'ed to use flock and Dovecot doesn't
It's conceivable that the different locking strategies of UWIMAP and
Dovecot don't matter because they would never be going after the same
mail files (right?) but there is procmail, which has to interact with
both. It appears to not use flock OK, even though the docs say it
should since UWIMAP expects it, and I've disabled lockf as well. But
will there be a conflict with procmail and dovecot's use of fcntl,
which UWIMAP doesn't use?
Help.
3) I occasionally see "Disconnected for inactivity" message. How long
before that happens? Is the interval configurable?
Thanks to all. A brother sysadmin was stunned by performance gained in
Dovecot. He has to keep postmaster messages for a period and filters
them into a separate folder...over a long weekend this folder could get
to 1500 messages and 150MB...with UWIMAP he could only delete approx 800
at a time and then had to wait 5-10 minutes for it to process. With dc,
he marked off the whole folder and it was gone in seconds.
--
====
Stewart Dean, Unix System Admin, Henderson Computer Resources
Center of Bard College, Annandale-on-Hudson, New York 12504
[EMAIL PROTECTED] voice: 845-758-7475, fax: 845-758-7035
