Bulk adding users in linux

So while I’m no Linux admin I end up having to do the odd thing on test servers, which generally involves some head scratching and googling as I do it so rarely. So this is one for the time vault as I really doubt I’ll be adding users to a server on a regular basis.

The problem was a couple of new test servers needed to be created and everyone in the team given a login. Now there’s talk of a jumpbox coming but in the mean time I needed a quick way of creating all the users and of course there’s a command for that newusers which can be passed in a file with the users listed.

An example line in the file would be

david:david:607:607:david:/home/david:/bin/bash

So that’s

1. Username
2. Password
3. User Id
4. Primary Group Id
5. Display name
6. Home Directory
7. Default shell

Beware the copy and paste monster on this one, I got busted by forgetting to change the user id’s and therefore actually set everyone up as the one user… DOH

The next thing was to add all the users to a particular group, wheel for example. I could set it as the primary group in the above file but I wanted to add to the secondary groups. I couldn’t find anything so I created a little script that just runs the commands

#!/bin/sh
sudo usermod -G wheel david

Just add a line for each user