Re: Dynamic to basic disk?

Shenan Stanley wrote:
Not to mention that the only time a MIRROR RAID does anygood is
during a hardware failure

Anteaus wrote:
True, and sometimes not even then. I had a situation where a
Netware server suffered a disk controller-card failure in a
mirrored pair, and the 'death thrash' of its SCSI controller
corrupted the other disk too. The only advantage of the mirror was
that I was able to get the backup software to run from the
partially-corrupted disk, which avoided having to start from bare
metal. But, I still had to use a tape backup.

One of the strongest arguments against RAID of any kind is that in
most cases it precludes the use of disk-imaging utilities. This
makes it much more difficult to have any kind of rapid-recovery
plan in place. If the array does break then you're facing the full
downtime of a bare-metal rebuild, possibly several hours, maybe a
day or two. Whether this is acceptable obviously depends on the
role of the machine, and how much the downtime will cost in terms
of idle staff.

I have used Symantec Ghost (8.2) a few times this past week on a striped
hardware RAID and once on a hardware RAID5. I have had no issues using
imaging products to make/apply images from/to hardware RAIDed systems.
After all - if the hardware is doing the work - the imaging application
doesn't know any different. I have also used Veritas (Symantec now) to do
similar restores (bare metal included with their product add-on) to such
systems. Some server systesm, some higher-end workstations.

I am not pushing Symantec here - it is just my most recent experience with a
RAID (hardware) setup and imaging products. Since I can boot some of the
same systems with BartPE (with proper drivers injected) and see the data
from there on the hardware RAID - I'm sure many other things are possible
with the hardware RAID...

--
Shenan Stanley
MS-MVP
--
How To Ask Questions The Smart Way
http://www.catb.org/~esr/faqs/smart-questions.html


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