Today I’ve noticed a strange thing after Directadmin software update. Exim stopped processing e-mails, the thing that is really necessary for any server. I’ve started to look through log files to identify the problem. Here is what I have at the moment.
My mainlog (/var/log/exim/mainlog) is full of messages like this:
2008-10-30 19:27:02 exim 4.67 daemon started: pid=16453, -q15m, listening for SMTP on port 25 (IPv4) port 587 (IPv4)
2008-10-30 19:27:03 1KvZad-0001Ra-TE unable to set gid=12 or uid=510 (euid=8): domain_filter router (recipient is email@example.com)
2008-10-30 19:27:03 1KvZad-0001Ra-TE internal problem in domain_filter router (recipient is firstname.lastname@example.org): failure to transfer data from subprocess: status=0100 readerror=’Success’
Messages are not delivered and I’m trying to investigate the issue. paniclog has messages similar to the shown above.
What are the ideas? First of all I’ve checked all the file permissions and they were ok. I’ve compared them to the permissions of a working server and found no difference. Then I’ve checked domain_filter setting of exim.conf: everything seems to be good too.
The idea came from one of the numerous mailing lists. And it was simple enough to solve my issue. I just had to add a suid bit to exim executable with one command. Here is what I had before:
The command I had to enter was chmod u+s exim
This solved all the issues after exim reboot. The most strange thing is that at another server such a software update came without anything like this: all the permissions were OK. Just preventing you from spending so much time: if you’re getting a problem like this, most probably you will be able to solve it with one single command.