dd of mounted filesystem

Drew Tomlinson drew at mykitchentable.net
Thu Dec 11 12:24:24 PST 2003

----- Original Message ----- 
From: "Dru" <dlavigne6 at sympatico.ca>
Sent: Thursday, December 11, 2003 11:54 AM

> Can anyone describe or point me to resources explaining why it is
> dangerous to dd a filesystem while it is mounted? Is it still
> to be dangerous if the system is first dropped down to single-user

I'm guessing between this thread and your "unmounting /" thread that
you're attempting to duplicate your root drive?  I just tried this in
single user mode a few days ago with dd and it didn't work.  The
resulting file system was "dirty" so I used 'fsck' to clean it.  The
results were a complete unusable mess.

I tried another method described in my thread "Trouble Adding New Boot
Drive" but couldn't quite get it right.  However I think I'm overlooking
something quite simple.  You might like to look over the steps I took
and see if they make sense.  Then if you get it to work, I'd be most
appreciative if you'd let me know what I missed.  I'll send the message
to you if you want.

Good Luck!


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