Category Archives: Linux Administration
Utility df shows inconsistent calculation for ext filesystems
The output of “df” might sometimes seem inconsistent or wrong and especially in some situations the presented information seems to obviously not match up. The fact is, the information is not wrong but the calculation behind it considers facts that … Continue reading
Replace section in file with content from another file
While automating things, you might come across the need to replace a block of lines within a file – like replacing a section with IP addresses you want to block in an .htaccess file. Automating this task means replacing this bunch of … Continue reading
Gitosis Arguments to command look dangerous
Dealing with non-English languages, you might come across a couple of issues caused by special characters. Even gitosis has its limitations in this area. One of the error messages caused by special characters is: “Arguments to command look dangerous”. When a … Continue reading
Resize Proxmox VM disc via command line without LiveCD
To increase the disc size from the command line, login to the Proxmox host. In the command line you can list the VMs configured by this command to find the VMID needed. For this example the VM with the VMID … Continue reading
Monit restart not working on CentOS – no pid-file after restart
Monit is a monitoring tool that can monitor processes, files and more. In the event of a failed monitor, monit is able to alert or trigger an action. Often the action triggered is to restart the monitored daemon. With the … Continue reading
Gitosis Unsafe SSH username in keyfile
While configuring and using Gitosis you will probably see the following error sooner or later. This error will appear immediately when changed configuration is pushed to the gitosis-admin repository. With this error, the reported user keys are not provisioned properly … Continue reading
Add a line into a huge file
Handling huge files can be a massive challenge. In a previous post I have shown how to remove a range of lines from a huge file (which can also be used to just read a number of lines out of the … Continue reading
Git repository cluster setup – Part 2
A git cluster with more then two servers with the approach described in Git repository cluster setup will increase the time you need to push changes to the cluster. This is because of the mirroring back. To solve this a more advanced version of the script is needed to avoid that the mirror-server would try to mirror the changes back to the master-server. Continue reading
Keep track of Linux configuration changes with etckeeper
The configuration of a linux server will change over time. Keeping track of the changes of all the configuration files can be a challenge. etckeeper is a utility that makes this easy. With the help of etckeeper, the complete /etc/ directory is placed … Continue reading
Replace hard disk from software RAID
A hard disk is one of those components that will fail at some point in time. To protect against data loss in such a situation you might have already configured a RAID array. Eventually, you’ll have to replace a malfunctioning hard disk, … Continue reading
