Linux

Restoring your Qmail mailbox settings on PLESK

Posted by marcus on Apr 23, 2009 in PLESK | 1 comment

Screw up your email settings? it happens to the best of us.

PLESK has a handy little app that reverts your mailbox settings back to the settings in the PLESK database, and makes sure permissions, etc. are correct.

LibClamAV Warning: Cannot dlopen: file not found – unrar support unavailable

Posted by marcus on Apr 7, 2009 in Linux | Comments Off

We encountered this error recently when upgrading our ClamAV to 0.95 and ran into a problem where we got the error :

LibClamAV Warning: Cannot dlopen: file not found – unrar support unavailable

The solution to this is quite simple:

Linux Commands : Argument list too long

Posted by marcus on Mar 26, 2009 in Linux | Comments Off

There may come a time where you try to run a command on many files in a folder and you’ll get this annoying message similar to this:

-bash: //bin/chown: Argument list too long

The reason for this annoyance is that Linux kernel has a limitation of bytes it can process through as arguments in exec() commands. Try:

[root@x folder]# egrep ARG_MAX /usr/include/linux/limits.h
#define ARG_MAX 131072 /* # bytes of args + environ for exec() */


And you’ll see what I mean.

Filter spam to a folder with procmail and qmail

Posted by marcus on Feb 25, 2009 in Mail | 33 comments

This post is inspired by Russ Whittmann and Europheus’ solutions , with these goals/improvements in mind:

• Move spam marked by spamassassin into a special Spam folder in each account (flabergasted this isn’t standard on something like PLESK!)
• Allow for quota, which is available on some PLESK servers (I previously thought it was available on all servers until recently) .
• Make a solution with as minimal manual labour as possible outside the PLESK control panel, which relates most specifically to having to edit and create .qmail and .procmailrc files each time you change or add an email account.
• Avoid having to have a special .procmailrc file for every user, one recipe for all!

How to Set Up a Backup MX Mail Server on PLESK

Posted by marcus on Feb 23, 2009 in Mail, PLESK | Comments Off

It’s possible to have a server act as a backup server, so in the unfortunate event that your main mail server goes down, mail gets queued up on the backup server until the main one is fixed.

Setting up PLESK to act as a backup MX server is fairly easy, here’s what to do.

Queue management with qmail/plesk

Posted by marcus on Feb 6, 2009 in Mail | 2 comments

Here’s some handy tips for managing your qmail queue on a linux machine, which can be helpful for debugging: