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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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Some months ago, I built a small VSAN home lab. Gradualy I expanded the setup - e.g. I moved from a hybrid setup (HDDs and SSDs) to all-flash (SSDs only) to utilize deduplication. Because errors might occur during testing, my NAS is still used as shared storage for the cluster. The HDDs of my NAS were unable to meet …

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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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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 …

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