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Reset Root Password on OpenSuse

If a normal user forgets his password it can be reset by root. But if root forgets it’s password it is not that easy. But there is a way. You need to boot your system into recovery mode to circumvent the login process. This is only possible if you physical access to the system (or the console of a VM) and may reboot the system. Enter Grub Menu While the system boots you need to enter the grub menu.

Manage Service with SysVInit

SysVInit is the predecessor of systemd and is responsible for starting, stopping and managing services. Where systemd uses configuration-files, SysVInit uses bash-scripts to manage services. These Scripts are located under /etc/init.d/* or /etv/rc.d/init.d/*. Check if SysVInit is running The initsystem has always the pid 1. So you can simply check the name of the process number 1 and see what you init system is. [tux@server]$ ps aux | head ... /sbin/init Unfortunately this doe not certainly mean, that you are running SysVInit.

Change Crypto Policy

Your OS will only accept a limited number of cryptographic algorithms. That way you will only use algorithms that are considered safe. This is really important. Otherwise you might think your are using an encrypted connection while in fact it is easily hackable. Ideally you should never need to change this settings and replace the algorithms with a newer one instead. But sometimes that is not possible. I had an example where a root certificate used an old encryption algorithms and I had no control over this certificate.

Restic OpenSource Backup-Tool for Linux and Windows

Restic is a backup-tool written in Go and compatible with Windows and Linux. From a user-standpoint it is kind of similar to Borg-Backup, with some differences, for e.g. that a repository can be shared with multiple hosts for better compression and deduplication. And since it is written in Go it is faster than Borg which uses Python. Installation There are a few ways to install restic. On Fedora you could install it with dnf but the packages is a few versions behind the upstream.

Stages in Dockerfiles

If you want to compile your Program while building your Container but don’t want you source code to be part of your image, you need to use stages. Why should I want that? My biggest concern is, that your container image gets small if it does only contain the binary and not all of the source code and temporary file from building it. That helps with download and creation-speed. On the other hand one might fear that his source code gets extracted if someone gets access to the image.