LVM Remove physical volume from volume group

LVM provides flexibility to organize logical volumes without being bound to inflexible partitioning. If set-up correctly, the LVM can grow as the disk/raid might grow. To allow the LVM to grow, the block device needs to be added as a … Continue reading

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Remove files from git history

When a repository contains files which should have never been committed, it is hard to remove them from the history as git is built to keep a history, not to change it. The following procedure will explain the procedure to … Continue reading

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Docker container on RHEL fails to start without error

Recently a Docker container refused to start for me without any hint about why in the OS or Docker container’s logs. It turns out that SELinux jumped in and blocked access without logging its interference. Containers which were running in … Continue reading

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Set the iLO password from Linux using hponcfg

No matter if you are looking for a way to manage the iLO settings from the Linux command line or just have lost or forgotten the iLO password, as long as you have access to the Linux system running on … Continue reading

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Create and merge git branches

Following the philisophy of git, branching is an essential and much used part of the development procedure. When a new feature is developed or a bigger change is to be implemented, a branch is created to work on and later … Continue reading

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Setup LVM and create logical volume

Creating an LVM on a disc / partition allows for a lot of flexibility in managing the storage. Managing a disc using LVM consists of a number of steps, from preparing the disc itself until mounting a volume. With LVM … Continue reading

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Extend logrotate for additional log files

The Linux operating system consists of many different components. Many of them log their activity directly or indirectly into log files. Over time those log files grow and would eventually fill up the disk if there wasn’t a utility like … Continue reading

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Manage SELinux boolean policies

Configuring a new service often means dealing with SELinux. The easiest way is most of the time to set an SELinux boolean. But what are SELiunx booleans and what exactly do they do? I will try to shed a little … Continue reading

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Find and extract one file from rpm package

Extracting a configuration file (or any other single file) from a package which is not installed is not a standard operation on rpm based systems, but with the following few steps, a file can be extracted without installing the package … Continue reading

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Auditing Linux system security using lynis

Lynis is a security auditing tool for UNIX and Linux based systems. It performs a security scan on the system and provides suggestions for best practices for system hardening. The report from lynis shows a lot of suggestions to harden … Continue reading

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