LinuXia

This article describes how to enable TLS support for Exim as server on Debian with the split configuration model. /usr/share/doc/exim4-config/README.Debian.gz already contains a fairly good description of that setup (currently in section 2.2).

First step is to put the SSL key and SSL certificate into /etc/exim4:


erebus:/etc/exim4# ls -l exim.*
-rw-r----- 1 root Debian-exim 960 2009-07-03 11:10 exim.crt
-rw-r----- 1 root Debian-exim 887 2009-07-03 11:10 exim.key


Maildrop exits in certain cases with exit code 75. This signals a temporary error to Exim, but no further
explanation can be learned from the exim log file:

2009-06-09 11:58:32 1MDy6C-0003Lm-Ky == racke@linuxia.de R=virtualuser T=vinson_virtualuser_drop defer (0): Child process of vinson_virtualuser_drop transport returned 75 (could mean temporary error) from command: /usr/bin/maildrop

For better diagnosis, add the log_defer_output and log_fail_output options
to the corresponding pipe transport, e.g.:

There is a plugin at Nagios Exchange to monitor Exim's Mail Queue:

check_eximailqueue.

Put this script into your Nagios plugin directory. Adjust the paths to utils.sh and the exim binary if necessary.

On Debian you need to install nagios-plugins-basic first and use the following
paths:


. /usr/lib/nagios/plugins/utils.sh

EXIM=/usr/sbin/exim4

Install sudo if necessary.

One of my customers reported this morning that their webserver was unusually slow. I discovered that it was abused for sending SPAM through web forms. The PHP script processing these forms lacked proper input sanitization. After disabling the script by renaming its mail function I deleted almost 1000 of SPAM emails from the queue:

xxx:/var/spool/exim4/input# grep -l "Email von yyy.zz:" *-D | perl -pe 's/-D$//' | xargs exim -Mrm

To avoid unnecessary DNS lookups for the hostname of the machine, define primary hostname:

primary_hostname = linuxia.de

Or you can use on of the alternatives described at:

http://wiki.debian.org/PkgExim4UserFAQ#head-9df4f560713a5f58d5cdb9fdf230...