Linux

Command su

sudo su - some_user

is short for

sudo -s -u some_user

Breakdown:

  • -s -> run the shell specified in the environment variable SHELL if set, else the user's login shell.
  • -u -> run the command as the specified user rather than root (-> sudo su - )

Another useful command:

sudo su - some_user –c command_you_want_to_execute

which executes the single command_you_want_to_execute with some_user privileges.

SCP file transfer

It is relatively common that after you ssh into a machine you need to switch to a different user via sudo su to be able to do stuff. Along with this there might be a need to download files. This is not possible in one go. You need to copy your file somewhere where your default ssh user also has access (try /tmp) and then do a regular scp using that path:

scp my_ssh_user_name@my_company.com@your_ip_address:/tmp/your_file.txt .

The above copies your_file.txt to the current directory -> .