This question already has an answer here:
sudo from a standard user works fine, but when I try to use it from
root it returns this error:
sudo: can't open /etc/sudoers: Permission denied sudo: no valid sudoers sources found, quitting
/etc/sudoers has the appropriate 755 attribute and owned by
root:root I even recreated it with
visudo, all fine, but error persists. /etc is 755 and also owned by root:root, I even tried to reinstall sudo: no difference.
I need to sudo from root because I use a python script which uses sudo to run os privileged commands. But now I'm running that python script at boot time and it crashes due to this issue. I installed the same version of the OS in a Virtual Box VM and it works fine.
What can be keeping root from running sudo?