was network prob, now unknown prob: Now permissions prob

Les Gray lgray at bigpond.net.au
Sat Sep 15 12:35:43 BST 2007


On Saturday 15 September 2007 20:59:01 James Takac wrote:
> Ok
>
> I believe I now know what caused my problem. Not creating a mount point on
> the new drive and then changing permissions of the / (root) directory is
> likely where I went wrong. I've booted into recovery mode and did
>
> chown root:root /etc/sudoers
>
> which has returned my ability to do admin tasks and reafirms in my mind
> that I likely messed up the permissions when adding my new hard drive a few
> days ago and is recoverable.
>
> I believe I may have inadvertently done the following
>
> sudo chown -R USERNAME:USERNAME /
>
> I think I messed up there. Would it put things right if I replaced username
> with root? I'll do some more googling in the mean time just incase I can
> get all the way

Hi James,

Running 'sudo chown -R USERNAME:USERNAME /' changes every file on your system 
to have owner and group 'USERNAME'. Putting 'root' in instead of 'USERNAME' 
means root will take ownership of everything.

You want neither of these things to be the case.

If this has already happened by the time you read this, then I'm sorry to say 
but you have one almighty mess on your hands.

Do you have a partition image(s) of your hard drive? If so, then the easiest 
thing for you to do is to restore your system using these image(s), 
remembering to back up any files you want to keep to some other medium. You 
can change the permissions on this hopefully small number of files later, 
once you have your system back.

If you don't have stored partition images, then a reinstall is the best 
(only?) option.

I recommend a program called partimage for backing up disk partitions. You can 
get it (among other places) on the bootable 'System Rescue CD' - 
sysresccd.org .

As you probably know, you should never have any cause to change the 
permissions of / . Using the '-R' option means the change is recursive ie. it 
includes every file and directory below / . In other words, your entire 
system. A definite no-no.

If your new drive won't mount because of permission problems, all you need to 
do is change the permissions on the mount point. For example, you want to 
mount your disk on /media/newdrive. All you need to do is run 'sudo chmod 
777 /media/newdrive'. This will make everything on that mount point 
readable/writable/executable by all users. If you are the only user this is 
not a problem. If there are other users you may want to adjust the 
permissions accordingly.

HTH

Les



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