Compaq 18,2GB drive compatibility

Hello,

I have a raid5 with Compaq 18,2GB 10k Ultra3 drives from Seagate
(BD0186349B) and need to replace a drive. Do I have to use the same
model or can I replace it with another 18,2GB 10k U3 drive Compaq used
for their servers like a Fujitsu?

Thanks,
Mike

On 28 Jun 2006 13:21:40 GMT, Michael Perkonigg wrote:

>Hello,
>
>I have a raid5 with Compaq 18,2GB 10k Ultra3 drives from Seagate
>(BD0186349B) and need to replace a drive. Do I have to use the same
>model or can I replace it with another 18,2GB 10k U3 drive Compaq used
>for their servers like a Fujitsu?
>
>Thanks,
>Mike

You will have to replace it with a drive that has the same Compaq
spare part number. The manufacturer of the drive should not matter, as
long as it identifies itself as a Compaq/HP model.


Aidan Grey

* Michael Perkonigg:

> I have a raid5 with Compaq 18,2GB 10k Ultra3 drives from Seagate
> (BD0186349B) and need to replace a drive. Do I have to use the same
> model or can I replace it with another 18,2GB 10k U3 drive Compaq used
> for their servers like a Fujitsu?

Basically you can replace the defective drive with any generic SCSI
drive that has at least the same capacity than the dead drive.

Benjamin

On 2006-06-29, Benjamin Gawert <> wrote:
> * Michael Perkonigg:
>
>> I have a raid5 with Compaq 18,2GB 10k Ultra3 drives from Seagate
>> (BD0186349B) and need to replace a drive. Do I have to use the same
>> model or can I replace it with another 18,2GB 10k U3 drive Compaq used
>> for their servers like a Fujitsu?
>
> Basically you can replace the defective drive with any generic SCSI
> drive that has at least the same capacity than the dead drive.

I already knew that, the question was meant more like: Do other Compaq
18,2GB disk drives with different Compaq model numbers have the same
capacity so I can use them as a replacement?

Regards,
Mike

On 2006-06-28, Aidan Grey <> wrote:
> On 28 Jun 2006 13:21:40 GMT, Michael Perkonigg wrote:
>
>>Hello,
>>
>>I have a raid5 with Compaq 18,2GB 10k Ultra3 drives from Seagate
>>(BD0186349B) and need to replace a drive. Do I have to use the same
>>model or can I replace it with another 18,2GB 10k U3 drive Compaq used
>>for their servers like a Fujitsu?
>>
>>Thanks,
>>Mike
>
> You will have to replace it with a drive that has the same Compaq
> spare part number. The manufacturer of the drive should not matter, as
> long as it identifies itself as a Compaq/HP model.

Well, I have drives with the CPN 176493-002 and would like to
replace one with 180726-002, is that possible?
Both are 18,2GB 10k U3 drives from Compaq.
Or is the only possible replacement a 176493-002?

Thanks,
Mike

* Michael Perkonigg:

> I already knew that, the question was meant more like: Do other Compaq
> 18,2GB disk drives with different Compaq model numbers have the same
> capacity so I can use them as a replacement?

Certainly. There are dozens of HP/Compaq disk drives that are 18.2GB and
bigger. But since you wrote "RAID" I assume your disks are SCA, right?
Most HP/Compaq SCA drives come mounted on a sled or on rails for the
model of server they are meant to be. Putting a disk from a differen
HP/Compaq server/disk array in your array is usually unsupported from
HP. So there's basically no difference in using a non-supported
HP/Compaq disk and a generic SCSI disk, except that the latter usually
is cheaper and also has a longer warranty.

If your question was if any other HP/Compaq disk drives are supported
for your array, then just have a look at partsurfer.hp.com

Benjamin

* Michael Perkonigg:
> Well, I have drives with the CPN 176493-002 and would like to
> replace one with 180726-002, is that possible?
> Both are 18,2GB 10k U3 drives from Compaq.
> Or is the only possible replacement a 176493-002?

Why don't you check the disk size on the disk drive manufacturers homepage?

Benjamin

On 2006-06-29, Benjamin Gawert <> wrote:
> * Michael Perkonigg:
>> Well, I have drives with the CPN 176493-002 and would like to
>> replace one with 180726-002, is that possible?
>> Both are 18,2GB 10k U3 drives from Compaq.
>> Or is the only possible replacement a 176493-002?
>
> Why don't you check the disk size on the disk drive manufacturers homepage?

I tried. Seagate tells me how many sectors per drive it has, Fujitsu don't
but gives me the min and max sectors per cylinder and the count of
cylinders. Both is not enough to calculate the amount of sectors on
this drive.
Fujitsu has more cylinders though.

Regards,
Mike

"Benjamin Gawert" <> wrote in message
news:...
>* Michael Perkonigg:
>
>> I have a raid5 with Compaq 18,2GB 10k Ultra3 drives from Seagate
>> (BD0186349B) and need to replace a drive. Do I have to use the same
>> model or can I replace it with another 18,2GB 10k U3 drive Compaq used
>> for their servers like a Fujitsu?
>
> Basically you can replace the defective drive with any generic SCSI drive
> that has at least the same capacity than the dead drive.
>
> Benjamin

Wrong. Do NOT use a "generic" SCSI drive. You will bugger your RAID.

You can replace it with any Compaq/HP drive that is at least the same
capacity as the drive you are replacing, provided that: the drive is
recognised by the array controller.

So technically, you could use a Ultra2-SCSI 18Gb HDD or a Ultra320 146Gb
HDD, or anything in between

HP use about 4 manufacturors, but they all build drives with HP firmware.
Non HP FW, and your risk screwing up your RAID in an unpredictable manner.
I've only seen a non-HP drive used with a SmartArray controller once, and
the result was total data loss from the RAID, eventually, after 2 weeks of
failed backups.

* Jez T:

>> Basically you can replace the defective drive with any generic SCSI drive
>> that has at least the same capacity than the dead drive.
>>
>> Benjamin
>
> Wrong. Do NOT use a "generic" SCSI drive. You will bugger your RAID.

You obviously don't speak of experience, otherwise you would have
noticed that what you say is nonsense.

> You can replace it with any Compaq/HP drive that is at least the same
> capacity as the drive you are replacing, provided that: the drive is
> recognised by the array controller.
>
> So technically, you could use a Ultra2-SCSI 18Gb HDD or a Ultra320 146Gb
> HDD, or anything in between
>
> HP use about 4 manufacturors, but they all build drives with HP firmware.

Nope. Some use HP firmware (which is just a certain version of the
generic firmware which has been certified by HP and where the ID string
now shows "HP" instead of "Seagate"/"Fujitsu"/whatever), some just use
generic firmware.

> Non HP FW, and your risk screwing up your RAID in an unpredictable manner.

That's nonsense.

> I've only seen a non-HP drive used with a SmartArray controller once, and
> the result was total data loss from the RAID, eventually, after 2 weeks of
> failed backups.

So you had a _single_ case where a RAID in which you put a non-HP disk
in and that showed complete data loss and now you're claiming that this
is due to the disk? Of course you never thought about that there might
have been some serious hardware problem which is not disk related
because otherwise a data loss wouldn't be possible. Even on really
ancient SmartArray controllers like the SmartArray-2 which with a
certain firmwares just didn't recognize non-Compaq drives a non-COmpaq
drive didn't lead to total data loss. Mind you that RAID (except RAID0)
is there for protecting the system against disk drive failures, so it
would be totally stupid if a broken or wrong disk drive would result to
complete data loss. Especially with expensive server RAID adapters like
the Smart Arrays. But I understand is that due to lack of ability to
examine the real cause of data loss passing that to a non-HP disk drive
might look like a viable option. Same is valid for generalizing a single
experience of failure.

FYI: we have dozens of different RAID systems (most are HP) from
different ages at work and use HP and non-HP disks in them. Of course HP
doesn't _support_ non-HP disks in their RAIDs which means in case of
trouble they won't help you. But _all_ the RAIDs work fine with generic
drives. But then, we also have admins that at least have enough
knowledge to solve hardware problems instead of passing them of
something totally unrelated.

Benjamin