Increasing log retention in qmail’s qmail-smtpd

The default qmail toaster install wont give you much in terms of log data past a 20-30 minutes on a production mail server. It quickly becomes advantageous to increase the duration of log data. You will want to set the “s” and “n” options in multilog to accomplish this.

Open up your /service/qmail-smtpd/log/run file and change;

#!/bin/sh
exec /usr/local/bin/setuidgid qmaill /usr/local/bin/multilog t /var/log/qmail/smtpd

to this…

#!/bin/sh
#The "s16777215" option sets the size of the log file and the "n80" denotes the number of log file to keep on hand.
exec /usr/local/bin/setuidgid qmaill /usr/local/bin/multilog t s16777215 n80 /var/log/qmail/smtpd

Then you will need to restart multilog via supervise with the following command:
svc -h /service/qmail-send/log

Category: Email, Qmail | 1 Comment

February 25

[Dovecot] – Inotify instance limit for user exceeded, disabling?

Today I noticed a bunch of errors in the dovecot log stating “[Dovecot] – Inotify instance limit for user exceeded, disabling”. Apparently Inotify is used to notify
the client immediately after new message has been received. This typically happens after the IMAP client uses the IDLE command.

The solution:

[root@SERVER ~]# cat /proc/sys/fs/inotify/max_user_instances
128
[root@SERVER ~]# echo "256" > /proc/sys/fs/inotify/max_user_instances
[root@SERVER ~]#

Dovecot shouldn’t need to be restarted, but you can choose to do so…. or can you?

Category: Email, Linux, Qmail | 1 Comment

February 10

.qmail-default files with nonexistent catchall

On servers where a catchall has been setup using the qmailadmin web interface, it is possible for postmasters to delete an email account that was setup as a catchall account (in this case; johnsmith@example.com). When this occurs, the .qmail-default file is not updated. Assuming said catchall was already designated prior to removal, mail is accepted for any-random-user@example.com and messages are deferred when delivery to /home/vpopmail/domains/P/earthwire.com/johnsmith is attempted. This can cause the qmail queue to grow over time when you have many users with this scenario.

A problem /home/vpopmail/domains/P/example.com/.qmail-default file:

| /home/vpopmail/bin/vdelivermail '' /home/vpopmail/domains/P/earthwire.com/johnsmith

What a nonexistent qmail user directory deferral looks like;

/var/log/qmail/current:
@400000004b72cd931e35f0ac delivery 5362496: deferral: client_connect:_connect_failed:_2/user_does_not_exist,_but_will_deliver_to_/home/vpopmail/domains/P/example.com/johnsmith//can_not_open_new_email_file_errno=2_file=/home/vpopmail/domains/P/example.com/johnsmith/Maildir/tmp/1265814921.29239.qmailserver.maildomain.com,S=3149/system_error/

A quick solution(s):

Edit the /home/vpopmail/domains/P/example.com/.qmail-default so the user account path points to postmaster or another user that exists.

Category: Email, Linux, Qmail | LEAVE A COMMENT

February 1

Qmailadmin feedback

Thanks. It’s working now.

You have my sympathy for having to support the qmailadmin web
interface. I assume I have yours for having to use it…

-Random Client

Category: Qmail | LEAVE A COMMENT

David Laube's Blog

Every linux user has a /home directory.

Increasing log retention in qmail’s qmail-smtpd

[Dovecot] – Inotify instance limit for user exceeded, disabling?

.qmail-default files with nonexistent catchall

Qmailadmin feedback