• To view a user’s groups:
    “id [user]”
  • Add a user to a group :
    useradd -G {group-name} username
  • Add a user to multiple groups:
    usermod -a -G group1,group2 username
  • Change a users primary group:
    usermod -g group user
  • Add a group to a user
    usermod -a -G group user
  • Get a list of the groups:
    less /etc/group