Wow… I joked about this day coming, and here it is!
Google announced today about plans to develop it’s own operating system, Google Chrome OS, based on the Linux kernel and boasting promises of speed, simplicity and security. Oh, and it’ll also be open source.
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.
This has been tested on CentOS but should work on most distros:
Memcache is a caching mechanism for PHP which speeds up access to data by storing it in the RAM. Memcache runs as a server in a similar fashion to a database, except that data is not persistent in the long term. The great thing about Memcache is you don’t need to recompile php. Here’s some instructions on how to install and set it up.
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!
Here’s some handy tips for managing your qmail queue on a linux machine, which can be helpful for debugging:
Qmail-Scanner is a very versatile tool for linux which allows you to scan any email that passes your system with various brands of virus scanners, including the open source ClamAV. Alongside the more thorough scan and possibility to audit content, I find the archiving feature very useful.
One particularly useful bit of qmail-scanner is that you don’t need to recompile qmail for patching, which can be a mamoth task on PLESK run systems (specifically VPSes in Virtuozzo)
I’ve been setting up a Postfix/Dovecot solution on a linux Fedora 9 machine and ran into this problem.
A little snooping around led to this solution:
Dovecot requires the dovecot-mysql package to run mysql authentication. This problem is simply cured by installing it with yum:
yum install dovecot-mysql