Sudo

Use `visudo` to make changes to /etc/sudoers.

NOPASSWD does not work

If you set the NOPASSWD option for a user or group in sudo and it does not seem to work then you most likely have the order of statements wrong. The last statement in a sudoers file wins. Don't forget the files imported from /etc/sudoers.d. For example, the following will not work if noah is also a member of the sudo group becaue the sudo group definition comes after and overrides the NOPASSWD option.

noah ALL=(ALL) NOPASSWD:ALL

# Allow members of group sudo to execute any command
%sudo ALL=(ALL:ALL) ALL

The fix is to define the noah user options after the sudo group.

# Allow members of group sudo to execute any command
%sudo ALL=(ALL:ALL) ALL

noah ALL=(ALL) NOPASSWD:ALL

Set timestamp timeout

The following sets the timestamp timeout to 30 minutes for the given username, noah.

Defaults:noah timestamp_timeout=30

The following sets the timestamp timeout to 30 minutes for all users:

Defaults timestamp_timeout=30

No password

Allow a specific user, noah to sudo without a password:

noah ALL=(ALL) NOPASSWD:ALL

Allow all users in the admin group to sudo without a password:

%admin ALL=(ALL) NOPASSWD:ALL