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 …

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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 …

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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: 1$ ipa dnsconfig-show 2--------------------------------- 3Global DNS configuration …

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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 …

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Wordpress updates, themes and plugins can be installed very comfortable in the backend - unfortunately it is still required to specify FTP or FTPS connection information. Depending on your personal preferences or security policy FTP is often not an option - e.g. when you're maintaining a central directory for SSH users …

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During a fresh CentOS installation recently I had the problem that a system's network connection was not working reliably. Sometimes pings were possible, sometimes not. After it was possible to elimiate the firewall as commonly root cause, it turned out that the network connectivity was only working if the console is …

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Grafana offers the possibility to authenticate users against LDAP - make it quite easy to integrate the tool into existing directory services. I'm using FreeIPA as directory and authentication service in my lab and had to adjust some settings to authenticate Grafana access. The first step is to alter the main …

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An advantage of using Kerberos along with SSH is that it makes entering passwords obsolete when establishing connections. Unfortunately this is not working out of the box under OS X in the first place: 1$ kinit cstan@STANKOWIC.LOC 2cstan@STANKOWIC.LOC's password: 3 4$ klist 5Credentials cache: API:xxx 6 Principal: …

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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 …

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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 …

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