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Re: rescue bootable cd ???

On Monday 01 October 2007 23:13, Jim Crilly wrote:
> On 10/01/07 05:15:27PM -0500, C M Reinehr wrote:
> > I've seen the term before but don't understand exactly what COW means,
> > but I think I know what you're talking about. I had a failing disk drive
> > last Friday and had to boot my system off of a Knoppix disk to see what I
> > could salvage from my raid-1 array. Knoppix didn't seem to include the
> > smartmontools package but I was able to use apt-get to install it on the
> > fly and use it to diagnose which disk was failing.
> COW stands for copy on write, whenever a change is made to a block (or
> file maybe, I don't know what granularity unionfs uses) that block is
> copied somewhere else and the original left in place so that the update
> can succeed and the original still exists.  Sort of like an LVM snapshot
> only instead of being backed by a LVM volume the changes are only stored in
> memory.
> But yea, the short answer is that it allows you to make changes and install
> software on read-only medium like CDs. =)
> Jim.

Thanks, Jim! :-)
Debian 'Etch' - Registered Linux User #241964
"More laws, less justice." -- Marcus Tullius Ciceroca, 42 BC

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