On Sun, Jul 06, 2003 at 09:36:56AM -0700, Scott Petler wrote:
> Hi,
> I am using amanda to back up to a hard disk on my system and would
> like to protect the backed up disk from accidental erasure.  I thought
> one way to do this would be to mount it then run amdump, and then umount it.
> The disk is going to be vulnerable during the backup period, but "safe"
> when not doing a backup or recover.  
> 
> Is there a way to do this?  Or are there some permission settings that
> would prevent a rm -rf /* as root from erasing all of the backup disk?

In general, permissions are not checked for root.
So I doubt any setting of permissions would help.

Even root can not modify a file on a file system mounted read-only.
You could mount it rw during backup, ro other times.  The advantage
to mounting it ro is that you can still do recoveries from the backed
up data.

Putting umount/mount commands in  your cron might work.
I'd be worried that the umount and mount would fail if something
had a file open on that file system.  Some mount commands (possibly
FS type specific) may have an option to do a "remount".  This option
may let you change the properties of the mount without affecting open
files.  Note, I said "may let you", I've never tried it.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
 JG Computing
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