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#264970 - 11/09/2005 13:49 Storage SYstems
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
Suppose you have an external storage system, raid5, connected via SCSI to a very old HP Prolian 5000 (1997). Suppose the Proliant goes down due to Power Supply failure.

Suppose, waiting that the part gets replaced, that somebody decides to disconnect the external storage system, connect it to another proliant server (3500) in the naive hope it will recognize the raid5 chain; boot the proliant 3500, find out from Windows NT 4.0 disk manager that the disks are there individually, and not as a raid 5 chain, switch off the server, and reconnect to the Proliant 5000.

Now, I am back to work and find out what happened. Tomorrow I will get the part, and reboot finally Proliant 5000 . Will the raid 5 chain be there, with all data intact, or should shoot myself right away? In other words, are there chances that the raid5 configuration is lost, and if so, how can i recover it?
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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#264971 - 11/09/2005 14:29 Re: Storage SYstems [Re: Taym]
pgrzelak
carpal tunnel

Registered: 15/08/2000
Posts: 4859
Loc: New Jersey, USA
Having done time with old Compaq hardware... Assuming that you have a Smart Array Controller inside your disk array, the controller is what would configure the RAID5. As long as nothing was done to touch the disks (formatting, adding drive labels, etc.), you should be okay.
_________________________
Paul Grzelak
200GB with 48MB RAM, Illuminated Buttons and Digital Outputs

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#264972 - 11/09/2005 15:40 Re: Storage SYstems [Re: Taym]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 13884
Loc: Canada
Retrieve the RAID controller from the dead machine and have it ready to install in the new machine. That method should have a very high probability of working.

Now as to what NT does when it suddenly finds itself running on completely new and unknown (to it) hardware, well..

Cheers

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#264973 - 11/09/2005 15:42 Re: Storage SYstems [Re: mlord]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31181
Loc: Seattle, WA
Sometimes NT asks the question about writing some kind of a signature to a new disk, claiming it is harmless. Anyone know if THAT would harm his RAIDs?
_________________________
Tony Fabris

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#264974 - 11/09/2005 16:12 Re: Storage SYstems [Re: tfabris]
blitz
addict

Registered: 20/11/2001
Posts: 455
Loc: Texas
I had this exact same thing happen. We installed dummy hard drives into the RAID controller for the first boot. Then shut down and intalled the drives with data on them.

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#264975 - 11/09/2005 18:55 Re: Storage SYstems [Re: pgrzelak]
drakino
carpal tunnel

Registered: 08/06/1999
Posts: 7868
Loc: Seattle, WA
As Paul said, assuming it is an external unit that was connected to a Smart Array, simply connecting it to another Smart Array should bring things back. 1997 era storage products that were Compaq branded were just dumb SCSI disk holders, with no array intelligence inside them. Thus it was likely cabled to a Smart Array PCI card. Based on the age of the boxes, I'm guessing a 2/P or 2/SL.

Writing a disk signature to each individual disk would likely cause damage, including possibly complete data loss. I can't remember exactly where on the disk the NT signature goes to say for sure though.

One world of advice. Try and make sure the Smart Array controller you plug these disks into has at least the same, if not newer firmware then the controller they came from. That should help in the auto migration. If you want to check that everything worked right, make sure you have a SmartStart CD handy to boot to. That has the Array Configuration Utility on it, and will be a better test to see if things are back, before letting an OS poke at the disks. For servers of that era, SmartStart 5.5 is the last version they will boot, and it is free to download.
_________________________
Tom

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#264976 - 12/09/2005 09:10 Re: Storage SYstems [Re: tfabris]
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
Quote:
about writing some kind of a signature to a new disk, claiming it is harmless. Anyone know if THAT would harm his RAIDs?


Thank you all so much.
First of all, you're correct, the sorage system is a dumb disk holder, no intelligence in it. And yes, it is cabled to a SmartArray controller, so the raid configuration is all in there.Now, I can at this point wait that the machine is rebooted after changing the power supply adapter, so my only worries are about the NT signature.

Tony, that's my worry, in fact. I do not know if the signature was actually put in them, but I am assuming it was, since that is the first question NT disk manager asks and, as you mentioned, it specifically states it is harmless. So what would someone technologically naive do? Answer yes, I assume. No way to know since the person is not here now, so I am left here crossing my fingers. HP part should be here soon. Guys, waiting is a nightmare.
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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#264977 - 12/09/2005 11:43 Re: Storage SYstems [Re: Taym]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31181
Loc: Seattle, WA
I actually never bothered to find out exactly what it was that NT writes to the disk when it asks that quesiton. That's something I should probably know.

/me researches.
_________________________
Tony Fabris

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#264978 - 12/09/2005 12:09 Re: Storage SYstems [Re: tfabris]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31181
Loc: Seattle, WA
http://www.microsoft.com/technet/archive/winntas/support/diskover.mspx

"The disk signature is a unique number at offset 0x1B8 that Windows NT uses as an index to store and retrieve information about the disk in the Registry subkey HKEY_LOCAL_MACHINE \SYSTEM \DISK."

From other mentions in that article, I get the impression that it's four bytes at or near the end of the master boot record. So the next question is... Does tweaking four bytes in the master boot record ruin the RAID array?
_________________________
Tony Fabris

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#264979 - 12/09/2005 12:51 Re: Storage SYstems [Re: tfabris]
pgrzelak
carpal tunnel

Registered: 15/08/2000
Posts: 4859
Loc: New Jersey, USA
Also, the question is if it got that far. I always thought that you had to agree to add the header, and that only really happened in Disk Manager. If you just powered it on, it might see the drives (POST test), but it shouldn't do damage unless it prompted and was accepted.
_________________________
Paul Grzelak
200GB with 48MB RAM, Illuminated Buttons and Digital Outputs

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#264980 - 12/09/2005 13:23 Re: Storage SYstems [Re: pgrzelak]
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
Unfortunately the person realized the disks were there, indivudually, from NT Disk manager. So he actually got that far.
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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#264981 - 12/09/2005 13:35 Re: Storage SYstems [Re: Taym]
pgrzelak
carpal tunnel

Registered: 15/08/2000
Posts: 4859
Loc: New Jersey, USA
Oh... That's not good...
_________________________
Paul Grzelak
200GB with 48MB RAM, Illuminated Buttons and Digital Outputs

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#264982 - 12/09/2005 14:13 Re: Storage SYstems [Re: Taym]
Attack
addict

Registered: 01/03/2002
Posts: 578
Loc: Florida
If the drives did have the signature writen. R-Studio should recover the information but you will need a place to image all of the drives in your array. I used it to recover files on a friends mirror array after he had used a ghosting type program to change his partition size on the mirror.

http://www.r-tt.com/FAQ.shtml#q13

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#264983 - 12/09/2005 14:54 Re: Storage SYstems [Re: Attack]
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
THis is major help, Attack. Thank you. I'll try to have that sw ready in case of major disaster.
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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#264984 - 12/09/2005 23:30 Re: Storage SYstems [Re: Taym]
drakino
carpal tunnel

Registered: 08/06/1999
Posts: 7868
Loc: Seattle, WA
Good news. Replicated what happened in our lab, and the Smart Array didn't even blink. Here is what I did:

1. Ran around the entire lab for a while just trying to find an NT4 box still working
2. Found a Proliant 7000 with 2 hard disks in a RAID 1 on a Smart Array 3100ES controller
3. Pulled the disks out and moved them to the NT 4 Proliant 6500 with no Smart Array.
4. Opened Disk Administrator and said yes to writing the signatures.
5. Powered down the NT 4 box and moved the disks to the Proliant 7000
6. Booted the 7000, watched as it saw the disks and all the data on them

So it looks like the Smart Array ignores the MBR and only pays attention to the config data stored in the first 4-8mb of the disk.
_________________________
Tom

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#264985 - 13/09/2005 15:13 Re: Storage SYstems [Re: drakino]
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
Drakino, THANK YOU!
What can I say, this board, meaning all of you guys, is fantastic!

No need to say, the part is not here yet.
I spent the day in meetings discussing the political reasons why are we in such a situation: who was were, why happened what happened, and, to make a long story short, it's not a pleasant time here. And all this is caused, ultimately, by the fact that the department did not want to spend money in updatin the machines when they should have, or renewing the maintenance contracts on that old old box. Of course, when it crashed, they put pressure on a person who knew little on how to solve the problem.

Well, Drakino, your test results are comforting, very very much! Really, thank you!
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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#264986 - 13/09/2005 16:19 Re: Storage SYstems [Re: Taym]
pgrzelak
carpal tunnel

Registered: 15/08/2000
Posts: 4859
Loc: New Jersey, USA
Please note, these power supplies tend to go out in pairs. If you had multiple power supplies and replace one in a Compaq Proliant 5000, be ready to replace others. We just had a bunch of them fail here in some of our older machines. Just a word of warning.
_________________________
Paul Grzelak
200GB with 48MB RAM, Illuminated Buttons and Digital Outputs

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#264987 - 13/09/2005 17:27 Re: Storage SYstems [Re: drakino]
mlord
carpal tunnel

Registered: 29/08/2000
Posts: 13884
Loc: Canada
Wow!

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#264988 - 13/09/2005 20:28 Re: Storage SYstems [Re: pgrzelak]
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
Paul, thank you for the advice, totally appreciated. But you won't believe this: that machine has ONE power supply. Besides being 8 years old. And besides having no maintenance contract on it. This is to give you an idea, if you should ever need, of how narrow minded can organizations be. Oh, and I don't want to forget to underline how long ago I had requested funds to replace it: THREE YEARS. And I've been asking over and over. If I wasn't stressed enough for the most embarassingly obvious and predictable disaster that could haver happen, I would be happy it finally happened.

And the most ridiculous thing of all is that the new server is located two rack units above it, and migration was in progress when the old one crashed. No, I'm not joking. Really, I shouldn't, but I feel like laughing

And I don't want to mention now why our backup is not very useful in this particular case, because I am still too mad.

Really, guys, thank you again. This place is a breath of fresh air, expecially in days like today.
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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#264989 - 20/09/2005 08:30 Re: Storage SYstems [Re: Taym]
pgrzelak
carpal tunnel

Registered: 15/08/2000
Posts: 4859
Loc: New Jersey, USA
Did you ever get that power supply? How did this end?
_________________________
Paul Grzelak
200GB with 48MB RAM, Illuminated Buttons and Digital Outputs

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#264990 - 20/09/2005 09:10 Re: Storage SYstems [Re: pgrzelak]
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
Yes. Yesterday. And the new power supply was... broken! (broken connectors, precisely).

So, "Tomorrow" (how many times I heard this?) we'll get another, hopefully working, power supply.

I am going crazy after this. Really. I have no more words to express how frustrated I am.

Thank you for asking. I will definitely post here when I reboot the server. If I don't shoot myself before I get the part, of course.
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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#264991 - 21/09/2005 10:44 Re: Storage SYstems [Re: Taym]
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
... so, today's news is that the part is coming... tomorrow

This is endless.
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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#264992 - 24/09/2005 17:59 Re: Storage SYstems [Re: Taym]
Taym
pooh-bah

Registered: 18/06/2001
Posts: 2413
Loc: Roma, Italy
Yesterday the Power Supply arrived. Wrong model. But same specs, so we connected it and... Data was there!

Thank you again Drakino for testing, and keeping our hopes alive! And thans everybody for your help!
_________________________
= Taym =
MK2a #040103216 * 100Gb *All/Colors* Radio * 3.0a11 * Hijack = taympeg

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