Munin 2.0 has been released and a .deb package has even been backported to Debian Squeeze!.

Version 2.0 comes with a bunch of new features and scalability improvements. This how-to will explain how to install and configure Munin 2.0 using Apache and mod-fcgid on Debian Squeeze.

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Linux start up behaviour is driven by the so-called runlevels. It will use the default value provided in /etc/inittab for some systems (Debian…), or /etc/init/rc-sysinit.conf or some others (Ubuntu…).

This tutorial will show how to change the runlevel used during boot by modifying Grub2 start up prompt.

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As a sysadmin, most of my time is spent working on remote machines and different task. tmux is a terminal multiplexer, meaning it allows you to run multiple terminals in the same windows.

This tutorial will explain the basics features of tmux that should help you be more productive with your every day task.

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When enabling logs with HAProxy on a busy web site, hard disk space can quickly become a scarce resource.

The reason is that, most of the time, HAProxy is set to use local0 facility which tend to write logs to a bunch of files in /var/log such as messages…

Thanks to rsyslog, we will be able to canalize those logs to a more appropriate location and only once, saving a bunch of disk space.

This tutorial will go over the steps required to accomplish this set up.

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Using freeradius for authentication

Here I am going to consider that the freeradius server is set up correctly, meaning that you can already authenticate your users with freeradius using radtest utility.

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XL2TP

Now, let’s get on the next phase: XL2TP.

Packages Requirements

You can install xl2tp with the following command:

# apt-get install xl2tp

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Even though I pretty like OpenVPN, there is still some devices that might not support the TUN/TAP driver needed by OpenVPN.

Take IPhones, Android phones for instance, you need to root them in order to get that feature, assuming somebody has already cooked a ROM for your device.

L2TP is quite and old standard that allow setting up VPNs.

On the other end, it does not provide any kind of encryption mechanism, and as such, it is pretty common to get L2TP running over an IPSec link.

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When working in a chrooted environment, there is a few special file systems that needs to be mounted so all programs behave properly.

For instance, grub will need to access your disk devices….

While most special file systems might be mounted with:

# mount fstype -t fstype /tmp/chroot/mountpoint

Where fstype will be sysfs, proc, /dev is not following this rule.

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There is a few software that will use the editor command to find out what text editor to use. Example commands will be dch to add a new .deb changelog entry, revision control softwares when prompting for a commit message …

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5. Configuring Dovecot

Dovecot has its SQL configuration gathered in a separated file: /etc/dovecot/dovecot-sql.conf, so let’s edit edit with our settings:

# vi /etc/dovecot/dovecot-sql.conf

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