Do we need to reboot after adding a user to sudoers?

Question

Do we need to reboot after adding a user to /etc/sudoers?

Answer 1

No. It'll work with the next sudo command.

But if it does not work, you can avoid rebooting by running

sudo service sudo restart

Answer 2

I just did this and yes, I did in fact have to reboot. So, maybe the previous answer wasn't wrong, but it definitely isn't right 100% of the time. Writing this in case someone else is looking for the answer as I just was.

Answer 3

In CentOS 7 you can also Logout from the system with "exit" and Login again and the Sudoers will be updated.

I've tested on minimal installation but I believe it works in other targets and possibly other distributions aswell.

Answer 4

After add user to sudo group,

#su - root -c "usermod -aG sudo username;"

execute following command:

newgrp sudo

And after that you can use sudo in your commands in current session without need to restart.

Also if you are in a shell script and you want to execute command just after add user to sudoers, run following command instead:

#su - root -c "usermod -aG sudo username;"
sg sudo -c 'sudo command1; sudo command2;'

And If you don't want to reapeat sudo word in each command do as follow:

sg sudo -c "sudo -- sh -c 'command1; command2;'"
OR
sg sudo -c "sudo -- sh -c '
 command1
 command2
'"

Answer 5

In fact the only thing you need is to get a (new) login prompt, so using the following command works:

anyuser$ su -l <user>
user$ sudo <thenewlysudoedcommand>
... works...

But if you are logged in as GUI, then you need to logout & login again.

But, as with MOST linux tools you DON'T need to reboot the computer (that's a Windows thing).