Category Archives: sysadmin

Linux: query remote ntp (and show time difference)

Sometimes you just want to query a remote ntp server (and maybe see the difference between the two clocks). In this case you can use the tool sntp. From the sntp man page: The default is to write the estimated …

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OpenSSL Cheat Sheat

I know I know, there are plenty of openssl cheat sheets out there already1) But as I keep using googling it again and again to find the most useful openssl commands I decided to do my own – the first …

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Howto: Disable persistent Network Interface Names (Debian Stretch)

How to disable persistent network interface names in Debian 9 (Stretch) edit /etc/default/grub and change the following line GRUB_CMDLINE_LINUX=”net.ifnames=0 biosdevname=0″ afterwards run “update-grub“

View “raw” diff on Github

Viewing a “raw” diff in Github is easy – if you know how. If you are viewing a commit on github the URL looks something like this: Adding “.diff” to the URL will generate the raw diff for you …

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Quickly create a (swap)file on linux

The traditional way for creating a linux swapfile would be using dd to create an empty file e.g. A faster way is to use “fallocate” e.g. 1) Don’t forget the usually procedure for swapfiles: References   [ + ] 1. ↑ …

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Migration of OpenVZ Container to KVM Guest

This is a short tutorial how to migrate an OpenVZ container to a KVM Guest. Some ideas have been taken from other tutorials1) 2) , the other half has been extracted from grml-debootstrap which can generate a KVM …

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Moving to KVM

Since our beloved OpenVZ virutalisation technology is not moving in a direction we are comfortable with, we are currently evaluation several virtualisation technologies. One the the possible options is KVM. This is not a full tutorial about KVM, there are …

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Running “backticks” commands on remote servers

Sometimes it’s necessary to run a complex command on a remote server witch also includes some “backticks”. Usually these commands are interpreted by the local shell so you need to use a little trick to force execution on the remote …

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Resetting Supermicor IPMI system

In case the IPMI system on a Supermicro system is unresponsive, but you are still able to log into the main server, you can issue the following command(s) to reset the IPMI: # load the necessary modules (optional) sudo modprobe …

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MacOSX: Manually restoring TimeMaschine Backup

In case you are a CLI junkie as myself and want to restore some files from a time maschine backup manually with the CLI (or using the finder), you will notice that the restored files cannot be changed. The restored …

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