R.M. Evers wrote:

thanks for your reply. what do you mean with 'half a mirror'? i'm
planning to use 2 disks, fully mirrored. the first time i pull one out,
and put in a fresh disk i expect things to be ok. but what do you think
will happen when i put in a disk that has been used before as a full
mirror? or is this exactly the situation you're talking about? :-)

The raid controller writes some signature on a disk to recognize it.
When a disk is broken, and replace the disk with an empty one, the
raid controller recognizes which disk is new, and which is old, and
mirrors from the old to the new.

If, however, you used a disk before as half of a mirror, then there
is already a signature on the disk, and, in some obscure cases I never
found out, the raid controller takes the wrong disk as master...

The result is usually a complete disaster (just the one that you wanted
to avoid when choosing a mirror-raid system :-) ).

Just make sure that a disk you insert is really really completely
blank, or has never been inserted into that raid-system.



--
Paul Bijnens, Xplanation                            Tel  +32 16 397.511
Technologielaan 21 bus 2, B-3001 Leuven, BELGIUM    Fax  +32 16 397.512
http://www.xplanation.com/          email:  Paul.Bijnens AT xplanation DOT com
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