Performing simple Backups with Cfengine 3

Today I noticed that it might be useful to backup some folders on one of my VMs from time to time. At first I thought about creating a new cron job, but then I noticed that Cfengine 3 is running on that VM. So – why not letting Cfengine 3 do all the work? Writing […]... Read More

Setting up Ntop automatically with Cfengine 3

Recently, I had to use Ntop to analyze the network traffic of one customer file server. Ntop shows the traffic per interface and there per protocol, source IP and offers many other ways of showing you what happens in your network. Ntop is great; however, I observed this tool taking many system resources since it […]... Read More

Setting file permissions and ownerships with Cfengine 3

One of the most common tasks of a Linux sysadmin (or DevOp) might be setting file permissions and ownerships. In this blog I’ll show you how you can do that in a very simple but effective way with Cfengine 3. Writing the Cfengine 3 code for setting file permissions and ownerships body common control { […]... Read More

Creating new symlinks with Cfengine 3

Sometimes it is necessary to create new symlinks. The following code snippet shows you how to do that with Cfengine 3. Please note that there are several ways of achieving our goal, but the following one should be the most efficient one when you only want to set one symlink. Writing the Cfengine 3 code […]... Read More

Monitoring the Apache web server with Cfengine 3

During the last weeks I received a lot of positive feedback on my blog posts and the Cfengine 3 code snippets so I started to post them on Twitter. Especially my little article about monitoring the CPU load with Cfengine 3 gained some attention there, that is why I am very motivated to dive in […]... Read More

Setting ACLs with the community version of Cfengine 3

As you might already know the community version of Cfengine 3 is not able to set ACLs the “Cfengine 3 way”. So when you are using the community edition of Cfengine 3 you have to find another way of doing it.. such as running shell commands out of the Cfengine 3 scripts. I hope the […]... Read More

Deleting old files with Cfengine 3

Cfengine 3 can be used to tidy your systems up on regular basis. Depending on the time, day of the week of the file extensions you are able to define how Cfengine 3 shall delete old and obsolete files. In today’s example a code snippet is shown which deletes all .gz files in /var/log which […]... Read More

Monitoring the CPU load with Cfengine 3

The creators of Cfengine 3 claim that their configuration management tool is able to perform a basic monitoring of important states, such as the CPU load. And indeed, with the help of Cfengine 3 you possibly get rid of some monitoring checks and therefore relive your monitoring system. This is doable because cf-monitord runs in […]... Read More

Using environment variables in Cfengine 3

Every Cfengine 2 script of my company contains environment variables. They are essential for configuring most of the services running on the different servers. For porting those scripts to Cfengine 3 one day I wanted to know how to make use of environment variables in the latest version of the configuration management tool. Well, the […]... Read More

Simple reporting with Cfengine 3

Keeping yourself up to date about what is happening on your Linux systems can be quite time-consuming. Many sys admins therefore use a little trick: Since the most important logs contain all the informative stuff, many admins install logcheck which reports unusual happenings every 60 minutes via mail. In this way, the admins stay informed […]... Read More