5 tools you should not be able to run as root

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 Screen and tmux automatically create
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Short tip: remove Katello completely

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 utility removes all required packages, stored
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Short tip: Updating Pulp database after upgrading Katello

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: # tail /var/log/httpd/foreman-ssl_error_ssl.log [Wed Aug 17 09:42:51.536914 2016] [:error] [pid 3178] [remote 10.22.1.16:128] mod_wsgi (pid=3178): Target WSGI script ‘/usr/share/pulp/wsgi/webservices.wsgi’ cannot be loaded as Python module. [Wed
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Short tip: Middle mouse click under OS X

The middle mouse button offers extended functionality in the most software – e.g. it can be used in web browsers to open or close tabs. When using the integrated trackpad of a MacBook or the Apple Magic Mouse this will not work due to missing mouse buttons. To enable this functionality under OS X there is a free software
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Simple CMDB import using Icinga Director

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 automatically import and deploy host information. Using Icinga
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Install Icinga2, Icinga Web 2 and Icinga Director under EL7

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 has been released.
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Integrate source code patches into RPM packages

Rcently I packaged the software scponly for Enteprise Linux using rpmbuild and stumbled upon an error message: $ cd ~/rpmbuild/SPECS $ rpmbuild -ba scponly.spec checking for libgiertz… … /usr/bin/install -c -o 0 -g 0 scponly /home/cstan/rpmbuild/BUILDROOT/scponly-4.8-1.el7.centos.x86_64/usr/bin/scponly /usr/bin/install: cannot change ownership of ‘/home/cstan/rpmbuild/BUILDROOT/scponly-4.8-1.el7.centos.x86_64/usr/bin/scponly’: Operation not permitted make: *** [install] Error 1 error: Bad exit status from
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Short tip: sudo and vi(m)

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 and also utilities to reload the application
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Spoiled for choice: new HDDs for my NAS

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
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