Linux: File Ownership

Users and Groups

Linux makes use a users and groups. When looking at /etc/passwd you can see the user and group ids of all users on the system.

redhat:x:30582:30583::/home/redhat:/bin/bash
manali:x:30583:30584::/home/manali:/bin/bash
armtest:x:30584:30585::/home/armtest:/bin/bash

Each user is assigned a user Id and group id. The default group in Redhat is a group with the same name as the user.

The groups are defined in /etc/group. A user may be a member of more than one group.

redhat:x:30583:
manali:x:30584:
armtest:x:30585:

Files have a User and Group Owners. The test file is owned by user michael and group tes

-rw-rw-r-- 1 michael root 0 Aug 15 20:41 test

chown <newuser> <file>

chgrp <new_group> <file>