Usermod

sudo usermod -aG sudo <username>

usermod -a -G YOUR_GROUP YOUR_USERNAME

usermod -s /usr/sbin/nologin myuser
ssh and scp will fail

Related commands

• passwd

See also

• sudo, id, visudo, useradd, userdel, usermod, groups, passwd, chown, chmod, chgrp, groupadd, groupdel, Passwordless sudo, passwd (package), sudo --help