Forcefully stop hanging Foreman tasks

After a system crash I recently had the problem that Foreman had several orphaned tasks that could not be stopped from the web interface: Because I planned a Foreman upgrade this was pretty bad as it prevented the pre-upgrade check: # foreman-rake katello:upgrade_check … Checking upgradeability… Checking for running tasks… [ERROR] – There are 8
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Simple REST application with Python and Flask

Currently I’m spending a lot of time on automating complex application scenarios; during training I also starting learning about creating customized REST applications. The result was a tutorial which covers all stages of developing a small “RESTful” application: Concept/Definition Development Tests and documentation But, let’s start with the basics first… Crash course: REST in Peace REST
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System management with Foreman/Katello – Part 1: Introduction and installation

The last couple of years I spent a lot of time in managing Linux systems with Spacewalk and Red Hat Satellite 5. Because the application was superseded by the vendor, I investigated on migrations to the successor. Back in 2008, Spacewalk was published as upstream project to Red Hat Network Satellite. Since then, a lot of development happened thanks to the numerous
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Short tip: Removing orphaned SAN multipath devices under Enterprise Linux

Recently, I had to remove a SAN LUN on a physical Enterprise Linux system. The first step was to alter the multipath service configuration file (/etc/multipath.conf) and make the daemon reload its configuration: # vi /etc/multipath.conf … ESC ZZ # service multipathd reload Afterwards, the device was removed from the multipath topology: # multipath -l
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Monitoring Foreman, Katello and Red Hat Satellite 6

Foreman, Katello and Red Hat Satellite 6 users have multiple possibilities to monitor infrastructure health. Beside the Foreman host, also managed systems and defined software content are worth monitoring. Foreman dashboard Foreman/Katello and Red Hat Satellite offer a dashboard with some widgets that can be used for monitoring hosts and products. The widgets can be ordered and removed.
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Authenticate GitLab against FreeIPA using LDAP

GitLab can utilize LDAP to authenticate against a variety of directory services such as Microsoft Active Directory Domain Services or FreeIPA and Red Hat Identity Management. This post describes configuring and integrating into FreeIPA. By clicking Identity > User Groups > Add within the FreeIPA interface, an assistant for creating new groups is started. Create
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Manage VMware Photon OS containers with Foreman and Red Hat Satellite 6

Photon OS is minimalistic RPM-based Linux distribution which is focussed on running Docker containers. It was optimized for VMware platforms (Workstation, Fusion, vSphere, vCloud Air) – e.g. its Linux kernel offers a caching mechanism optimized for vSphere. Another characteristic is the customized package manager tdnf (Tiny Dandified YUM) which is similar to YUM but has also supports managing OSTree content (git-like versioned kickstartable filesystem content).
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CentOS 7 and the incorrect dist RPM macro

When creating RPM packages recently, I had the effect that package names on CentOS 7 were set incorrectly. For example, a package had the name pinkepank-0.6-1.el7.centos.x86_64.rpm but should have set pinkepank-0.6-1.el7.x86_64.rpm instead. As Enterprise Linux derivates (CentOS, Scientific Linux,…) offer binary compatibility to Red Hat Enterprise Linux, I prefer omitting distribution-specific tags in package names. In the RPM spec
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Short tip: FreeIPA looses global DNS forwarder

Recently I found out that Red Hat Identity Management (IdM) and FreeIPA tend to forgot their global DNS configuration after some upgrades. In my case, the global DNS forwarder configuration was dropped forcing external lookups to fail: $ ipa dnsconfig-show ——————————— Global DNS configuration is empty ——————————— IPA DNS servers: giertz.shittyrobots.loc, jason.shittyrobots.loc $ dig +short
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New project: IcingaBusylightAgent

The last couple of days I have been working on a new project I want to introduce: IcingaBusylightAgent. It all began with a new telephony system in our office. Instead of using physical phones, my colleagues are now using softphones. In addition to this, a gadget called Busylight representing the instant messenger status is mounted
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