Tips & Tricks


To see the currently running processes, RAM usage and processor load, you can use the htop command.

While htop is running, you can press:

  • h to see help

  • H to toggle the display of user process threads

  • q to quit

You can run htop in monochrome mode by launching it with htop -C (I noticed some problems when running htop inside tmux, and monochrome mode helped).


SSH key

You can use SSH key to log in to Calcus without password authentication. See the excellent and very detailed explanation on Arch Linux wiki or a shorter write-up in Ubuntu documentation.


You can use the ssh config file to assign an alias for the server, so that you won’t need to type the username and ip address each time you connect. Full instructions can be found on howtoogeek.

In short, you can put the following in your config file (~/.ssh/config, you may need to create it first), replacing your user name:

Host calcus
  User your-user-name-here

This will allow you to login or copy with:

ssh calcus
scp localfile calcus:remotefile

If you combine that with using an ssh key as suggested above, you will not have to type your password either.

Bash keyboard shortcuts

Bash supports a multitude of shortcuts. Below are some which I find very useful.

X + x mean that two keys have to be pressed simultaneously, while X-x means that they can be pressed sequentially.

  • ESC-. or Alt + . last argument of the previous command

  • Ctrl + r search history for the last command including the specified characters (searches as you type)

  • Ctrl + a / Ctrl + e go to beginning / end of line (useful when Home / End don’t work)