My USB stick is now full of backups, and I need to delete at least one to upgrade Nextcloud. I cant.
I try rm -f ./nextcloud-bkp_2017*
and I get:
rm: cannot remove './nextcloud-bkp_20171211.tar': Permission denied
So I try sudo rm -f ./nextcloud-bkp_2017*
and get:
-bash: sudo: command not found
I then try su
And, it asks for a password.
I have tried every password I know, and some I didn't.
It always comes up:
su: Authentication failure
I even try (without knowing if it's the correct app):
apt install sudoer
and, of course, get:
E: Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied)
E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?
Is there anything I can do?
Where did sudo go?