Enabling Root in Big Sur

It is there for me in Directory Utility. Maybe if you somehow found a "Directory Editor," it doesn't have an edit menu, but then that would be odd because it is one of the standard menus every app should have.

Why do you need to enable the root user. It is almost powerless in Big Sur, and you should be able to authenticate anything that would require root.

If you are trying to install software that tells you that you must install as root, you should get away from that software as fast as possible as the developer's are idiots.

If sudo didn't work for you, something is wrong. You don't need to enable the root user for any reason whatsoever.

You don't need to go anywhere in Directory Utility. Unlock the padlock and choose "Enable Root User" from the Edit menu.

Before you enable the root user, try this.

In Terminal enter,

sudo su

enter your password when requested and hit return.

You will see this prompt:

sh-3.2# 

You now have "root privileges."

Enter the tmutil command without using sudo.

tmutil setdestination smb://guest:guest@NAS_IPADDRESS/TimeMachineBackup

You are already requesting that with sudo.

Is you user account admin capable?