Getting started with Puppet Enterprise

Getting started with Puppet Enterprise

It all starts with a request for ‘a couple’ of Linux server to be set up, which is duly built manually and managed individually. Pretty soon you get a request for some more servers and before long you find that…

How to set up a shell script to monitor load averages

How to set up a shell script to monitor load averages

Here is a handy bash script that can be used to send email notifications when a specific server is under high load. In the event that there is no other monitoring solution in place this script can be scheduled as…

A look at CrunchBang Linux

A look at CrunchBang Linux

I’ve done quite a bit of severe distro-hopping to find a reasonable distro to use on an old Dell XPS M1330, which is my work laptop at the moment. I eventually figured out that I would like something light-weight but…

How to delete files by age

Say your server is low on disk space and you have a large amount of old log files that can be deleted to free up some space. You only want to delete files older than i.e. 20 days. mtime +20…

How to find large files

One of the beauties of Linux is that you can combine multiple commands to get exact results. For example if you have loads of files in your home drive, here’s how to find files larger than a certain size, listing…

How to set up logging in without a password between your Linux machines

How to set up logging in without a password between your Linux machines

It is very useful to set up passwordless logins between your Linux servers as it can be used for automated tasks, i.e. any cron jobs you may have that requires logging in on another host to run rsync without waiting…

How to extend a Linux LVM volume

How to extend a Linux LVM volume

So you have a system using LVM and you need to add some disk space to it. This can be done quite easily due to the greatness that is LVM. This example is a Debian-based virtual machine managed by ESXi…

Howto Symlinks

Howto Symlinks

Symbolic links, or symlinks, are quite useful. Symlinks can be use to point to files or directories. Any operation performed on a symlink is done on the destination that it points to, except removing the symlink. As an example of…

How to set up log rotation for Tomcat catalina.out log file

If catalina.out grows larger than 2GB it can cause Tomcat to crash, which is a bad thing. To avoid this you can set up log rotation. Create a new config file: Then specify the details of the rotation: What did…

Setting processor affinity using taskset

Setting processor affinity using taskset

Setting processor affinity can be very useful, for example where you have several processes running on a multi-processor server but you have one process that is important enough to warrant giving it an exclusive processor, while letting other less important…