Summary#

Using usermod(1)#

One command I use the most is the usermod(1) command. I generally just append group membership; using the -a flag, to give the user another group as opposed to making it their primary group.

usermod -aG <group> <username>

Verify Group Membership#

It’s good to verify group membership after adding a user to a group. This can be done using the id(1) command. This will show effective user and group IDs assigned to the user.

id

Below is the output from this command. Say I added the group sshuser. It would seem that command was successful based on the output.

In this output we’ll see the uid of the user with the username. I’ll see the gid or primary group of the user. Along with the gid and group names of any groups appended to the user.

uid=1000(exampleuser) gid=1000(exampleuser) groups=1000(exampleuser),998(wheel),1001(sshuser)