The Python Package Index (PyPI) website offers plenty of Python module source codes. To install these modules, it is needed to download and extract the archive and execute an installation script afterwards. Using the pip (pip installs packages) package manager, this process can be automated - e.g. for the nagiosplugin …

Read More

If you plan to restrict utilizing the root user under Linux, it is most likely that you will create sudo rules to allow certain users to execute administrative utilities. There are plenty of tools you really should not be able to run as privileged users - some examples: screen, tmux The famous terminal multiplexers GNU …

Read More

If you're testing the nightly builds of Katello, you might come into a situation where it is advisable to re-install the software completely. As the particular installation steps are automated using Puppet, there is also a dedicated utility which automates uninstalling the software in a clean way: katello-remove. This …

Read More

After upgrading Katello recently, I stumbled upon the following error when accessing the administration interface: The web server protocol told me that a database update might causes this issue: 1# tail /var/log/httpd/foreman-ssl_error_ssl.log 2[Wed Aug 17 09:42:51.536914 2016] [:error] [pid 3178] [remote …

Read More

In my last article I focussed on Icinga 2 and the new configuration utility Icinga Director. I mentioned that Icinga Director can be used to link Icinga to pre-existing Configuration Management Database (CMDB) systems to simplify data import. In this article we will create a little "dummy CMDB" with MySQL and …

Read More

Icinga2 is a very powerful monitoring system that can be used optionally with the new user interface Icinga Web 2. In comparison with Icinga 1.x, those tools have been developed completely from scratch - they have nothing in common with the legacy software stack. This year, a configuration utility named Icinga Director …

Read More

Rcently I packaged the software scponly for Enterprise Linux using rpmbuild and stumbled upon an error message: 1$ cd ~/rpmbuild/SPECS 2$ rpmbuild -ba scponly.spec 3checking for libgiertz... 4... 5/usr/bin/install -c -o 0 -g 0 scponly /home/cstan/rpmbuild/BUILDROOT/scponly-4.8-1.el7.centos.x86_64/usr/bin/scponly …

Read More

System administrators know requirements like this - a dedicated server needs to be deployed for a new application. In order to enable owners to maintain their application they need permissions to modify relevant configuration files. In this scenario, sudo rules are often configured in a way to enable file modifications …

Read More

2016 seems to be the year of big hardware renewals for me - after completely overhauling my virtual infrastructure, I also needed new hard drives for my NAS after nearly 4 years. NAS, DAS, what? For many years, I have been using D.I.Y. NAS servers for collecting my data and media library on a single host. After I was …

Read More

If you want to combine multiple terminal sessions on one window, multiplexers such as tmux or GNU Screen are useful tools. I have been using screen for 10 years with the following configuration: 1$ cat ~/.screenrc 2# F7+F8 for tab switching 3bindkey -k k7 prev 4bindkey -k k8 next 5 6# disable welcome 7startup_message …

Read More