In message
,
Wagg writes
I think it is a Raid 5, but will get him to check. Making a bit more
sense now! I will find out and post back if needed, if that doesnt
answer it all!
Hopefully he will have the HP array configuration utility loaded.
Opening that up will tell you exactly how the disks are configured and
make the lights on the disks flash to tell you which disk is in which
volume/RAID set when you select the controller, RAID set, volume etc...

-Ben

--
Clint Sharp

In message , Synapse Syndrome
writes
I've never seen the point of JBOD. Do people actually use it?
I've seen them a few times in commercial settings.
If one drive
fails, you lose everything (without having to go through a recovery
process - and what happens to files that span different physical drives?)
Not to be used for anything that isn't transient or backed up elsewhere
but the 'you lose everything' may not actually be that important
depending on the use it's put to.
,
and there is no advantage as far as I can see.
It's large, cheap and relatively fast storage that can be used as a
buffer for backup purposes or used for replicated systems where there is
no reason to have multiple redundant RAID sets because all servers
always have full copies of the data on the individual JBODs.

Perversely, the more you spend on storage the more likely you are to see
JBOD arrays.
--
Clint Sharp

In article b6a82516-5d34-4b1c-8f29-fe3431c8d8ca@
41g2000yqf.googlegroups.com, says...
Possibly the wrong groups, but not too sure where to post this
question. A friend of mine has a Raid array, with three 146gb drives
in a compaq server, and then three 36gb drives, below that. The drives
were not re done, as the originals were the 36's, and they were just
swapped around in the cage they are in, the 146's up front at the top,
but the old ones at the bottom, still with the OS on them. The new
drives were configured as extra partitions.

Now my question is, with the 6 drives, between the partitioning and
setup (done by a professional company I am told) there is a missing
amount of 200gb between all the drives. Now I know that you loose a
certain amount with formatting and all that, but 200gb? Someone I know
who works in raids and just raids said that it doesnt appear to be
configured correctly, but without him seeing it (he doesn't live
anywhere near me or my other friend!) he cant be too sure, so I am
asking, does this sound right?

The company who set it up to begin with says the missing part is
normal, even up to that size. Just all seems a bit off to me.

Depends which RAID mode, i.e. morroring or striped.

EG 2 80s in a mirror array would read as 80Gb (less a bit for
formatting). In striping mode would show as about 150Gb.
--
Regards
Jon

In article
, Wagg
writes
Possibly the wrong groups, but not too sure where to post this
question. A friend of mine has a Raid array, with three 146gb drives
in a compaq server, and then three 36gb drives, below that. The drives
were not re done, as the originals were the 36's, and they were just
swapped around in the cage they are in, the 146's up front at the top,
but the old ones at the bottom, still with the OS on them. The new
drives were configured as extra partitions.

Now my question is, with the 6 drives, between the partitioning and
setup (done by a professional company I am told) there is a missing
amount of 200gb between all the drives. Now I know that you loose a
certain amount with formatting and all that, but 200gb? Someone I know
who works in raids and just raids said that it doesnt appear to be
configured correctly, but without him seeing it (he doesn't live
anywhere near me or my other friend!) he cant be too sure, so I am
asking, does this sound right?

The company who set it up to begin with says the missing part is
normal, even up to that size. Just all seems a bit off to me.

TIA

-Ben


There are different types of RAID. However, 3 disks typically means RAID
5.

In RAID 5 a disks worth of storage in the RAID group is used by the RAID
to provide redundancy.

I.e. 3 x 146GB = about 265GB after formatting.

"loosing" 200Gb on a RAID of 3 x 146 and one of 3 x 36 sounds about
right.


BR
Don C