I have a strange problem in my Linux box (Suse). Recently I took over this box as admin even though I have no prior admin experience. Following is my issue

I had following users under 'root' group initially

user1
user2
user3

Since I did not like user ids under root group. I modifed these user's group to 'users' using

usermod

command. Then I realised that all their files were still under group 'root', so using root id changed their group for all the files recursively using

chgrp -R users <home>

Then after some time, users complained that they could not able to change ower of the files. But claimed they could able to chown earlier

user3 tried the following

$ chown user1 test.sh

and getting the following error

> chown user1 test.sh
chown: changing ownership of `test.sh': Operation not permitted

file test.sh is owned by user3 and under users group

-rwxrwxrwx 1 user3 users 36 2007-05-16 17:50 test.sh

But it is working under root id (I know it should)

Then I changed the group back to root using

> id
uid=1010(iriuser3) gid=0(root) groups=0(root)

> id
uid=1008(iriuser1) gid=0(root) groups=0(root)

Even chgrp is nor working. Giving the same error

Please let me know how to resolve this issue

Depending on your operating system, either a use can run chown to give ownership of a file to another user or not. Solaris, for example, does not allow chown to be run by any user except root. HP-UX will allow chown run by any user to actually change ownership of a file to another user. What OS are you running?

Thanks. I am using Suse Linux

On Solaris this behavior is tunable on a global basis via the rstchown parameter. HP-UX allows a more fine level of control via the setprivgrp facility.

What about Linux? I am using Suse Linux

Depends on the release. Linux is moving toward capabilities with chown controlled by CAP_CHOWN. See:
http://www.die.net/doc/linux/man/man...ilities.7.html
http://www.securityfocus.com/infocus/1400

Thanks Perderabo. By the way, what is the effect of creating a user id (say user1) with uid=0 (that of root)? Will it cause any issues or system crash?