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I am setting up multiple-machine backup plan and I was hoping to use a user called 'backup' on each machine as the backup destination.

My problem is, there is already a user called 'backup' on my machine.

What is it for, and can I hijack it for my own purposes?

root@frodo:~# useradd backup
useradd: user 'backup' already exists
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1 Answer 1

up vote 5 down vote accepted

I can confirm it's in a default installation, see the /usr/share/base-passwd/passwd.master file provided by the base-passwd package.

According to the documentation from that package, its' used for backup accounts without full root permissions (which is available at /usr/share/doc/base-passwd/users-and-groups.txt.gz and /usr/share/doc/base-passwd/users-and-groups.html):


Presumably so backup/restore responsibilities can be locally delegated to someone without full root permissions?

HELP: Is that right? Amanda reportedly uses this, details?

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