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Hello, I created a new user "rootNew" After creation I manually change the file /etc/passwd and gave the new user "rootNew" uid 0. Now I have 2 users with uid 0 (root,rootNew). "whoami" command return "root" for both users. How can I know which user is log in the system?
UIDs on a Linux system have to be unique. This means there can only be one single user having the UID 0. Creating a second user and assigning UID 0 to him will have no visible effect at best or result in some things malfunctioning. User root is the Linux superuser. You cannot clone this account. root must exist, be named root and have UID 0. End of the story.