Presentation and practical implementation of OpenSSH certificates to faciliate key based authentication of servers and clients.

How to revoke keys and certificates on OpenSSH to forbid their use in server and client authentication.

Description of filesystem and partition identifiers as alternatives to block devices such as "/dev/sdc3".

The system administrator can force a user to choose a new password on their next connection.

File diversions allow to avoid overwriting local changes to a debian package's file when updating the package.

Quick presentation of network link aggregation on Debian GNU/Linux.

This document describes the procedure to follow to have the BIND DNS server run in a chroot jail on Debian GNU/Linux.