I have two CentOS 6.8 servers running on VirtualBoxes.
On one, I can login as a regular user then use "sudo" to run administrator commands. I just add "sudo" to the front and all works as expected.
On the other, I need to first run "newgrp wheel", otherwise it nags me that I'm not in the sudoers file. Once that's done, all is well.
As far as I can tell, both systems are otherwise identical. The username in both cases has a primary group of "users" and is also a member of "wheel" and "apache" groups. The "wheel" group, of course, has been given "ALL" access via "visudo".
The only difference, if it's important, is that the first one is a VM on Linux, and I access it via Putty. The nagging one is a VM on Windows, and I access it via the VirutalBox screen.
It's not a very big issue, but I like not needing the extra step. Does anyone know what is going on here?