53

I've commonly seen references to a wheel user group online as well as when setting up my sudoers file. Does naming a group wheel imply something special about the group or is it just a name for a generic group used in the same manner that foo and bar are thrown about?

2
  • 2
    See unix.stackexchange.com/q/1262/22565 I'd be tempted to vote it as a duplicate? Aug 27, 2014 at 14:26
  • Whoever considers this question a duplicate may have missed the point. The linked question is about the name. This question is more about its role. I thought the difference was obvious.
    – Manngo
    Feb 16 at 1:56

2 Answers 2

38

Rather than have to dole out individual permissions on a system, you can add users to the wheel group and they can gain access to administrator levels, simply by being in the wheel group. It's typically tied directly into sudo.

## Allows people in group wheel to run all commands
%wheel  ALL=(ALL)   ALL

Which means you can do anything on the system with sudo <cmd>.

Previously you needed to be in the wheel group if you wanted to have access to use certain commands, such as su.

excerpt - Wheel on Wikipedia

Modern Unix systems use user groups to control access privileges. The wheel group is a special user group used on some Unix systems to control access to the su command, which allows a user to masquerade as another user (usually the super user).

3
  • 18
    Why is it called "wheel"?
    – Gherman
    Nov 1, 2019 at 16:38
  • 26
    The term was derived from the slang phrase big wheel, referring to a person with great power or influence. wikipedia
    – fracz
    Nov 8, 2019 at 7:50
  • 3
    Here's an alternative thought I had: On a ship, one can pass "The Wheel" to trusted subordinates to man the ship. It also has significance in terms of control but also added responsibility i.e. the steering wheel of car
    – robert
    Mar 25, 2021 at 14:15
9

Early on in the days of Unix one had to be a member of wheel in order to su to root. Used as an additional layer of protection for the system. I don't know of any special significance now, it is just a legacy like the uucp group.

Not the answer you're looking for? Browse other questions tagged or ask your own question.