Bash: Multi-dimensional Arrays

shell script
Learn how to simulate a multi-dimensional array in bash using an associate array with clever use of the hash key. Bash 4 only provides one-dimensional indexed and associative array variables.

Linux: Restrict su to Group

unix linux
Explains how to restrict the use of su command to a limited number of users belonging to a group.

Unix / Linux: Manage Multiple SSH Keys

unix linux
Manage multiple ssh private keys and configure ssh to map different private keys to different hosts automatically by using ~/.ssh/config configuration file