How Are RAID Arrays Identified By Hardware? 72
Coward Anonymously Before Me asks: "This is more of a tech/hack question, but recently my highpoint controller forgot my disks were in a raid array. All the Disks still function, and have ZERO problems, aside from being not identified as still in RAID-0. All the data should still be there, but remains unaccessible to me, thus the question how and where would this kind of information be stored? On chip? MBR? and can the data be recovered without 3rd party interaction via free/open source toolkits? or even purchased software?"
If you have a little coding experience... (Score:3, Interesting)
Uhh (Score:1, Insightful)
Re:Uhh (Score:2)
Re:vs RTFM (Score:4, Insightful)
Am I the only one who thinks that a Manual is a pretty lame source of information to reach for first-thing?
I have a few sources I go through, usually the manual is one of them, but I _Always_ first ask a person who might have the answer on hand. Manuals are not often things which lend themselves to answering typical questions such as "Can I blah?". The problem with "Can I blah" being looked up in a manual, among other things, is that often there are numerous synonyms for 'blah', and only one of them is ever used in the book, especially the index.
Perhaps they mean "Read the entire manual before even using the product". The obvious problem here is that manuals are getting longer every day. I've heard that some Linux Distro comes with a 2000 page manual just for getting it installed. Obviously, to read an entire manual before using a product would leave little time for using any products, and leave you more or less unknowledgeable about the product.
Then there's the problem of phrasing. Manuals may answer your question, but only burried in a lot of other information which isnt related to what you're actually working on. A person who knows already, however, can simply answer your question.
Slashdot, however, is far too public and non-specific. There's no reason to ask this kind of question on slashdot, get some friends or something.
Re:vs RTFM (Score:2)
So it's really a question of 14 hours vs near instantaneous.
If you dont pick instantaneous you're merely a fucking idiot.
Re:vs RTFM (Score:1)
Re:vs RTFM (Score:2)
Re:vs RTFM (Score:1)
It's been my experience, especially with simply coding questions, that it's easier to deja and google for competent Linux/Unix answers than it is for competent windows answers.
Of course, I often find more windows answers overall, it's simply that they just aren't very helpful [driverforum.com].
Re:vs RTFM (Score:1)
Re:vs RTFM (Score:2)
Re:vs RTFM (Score:1)
This is why things like FAQs exist, people are tired of answering the same questions over and over, when there are far more interesting things to do. #debian has the apt bot, for example.
Also, it depends on how you ask the question. If you think that people in support channel come there for answering every of your questions, you're mistaken and will be rightfully flamed.
BTW, manuals have an useful feature called "index". Maybe you could try using it.
Index problems (Score:1)
BTW, manuals have an useful feature called "index". Maybe you could try using it.
Grandparent wrote that many manuals aren't well-indexed: "The problem with 'Can I blah' being looked up in a manual, among other things, is that often there are numerous synonyms for 'blah', and only one of them is ever used in the book, especially the index" (my emphasis).
Whoops (Score:1)
About the synonyms problem. Some books I've got here have a short introduction in the form of "foo is also known as bar and baz, but for consistency reasons we'll call it foo". If it's hard to find information in a book then it's just not worth buying. And anyway there's always Google.
Re:Whoops (Score:1)
And anyway there's always Google.
But not everybody knows the secrets of forming a good Google query. Google is good, but not good enough to read your mind... yet.
Re:Whoops (Score:1)
'RTFM' is more polite when you name a chapter (Score:1)
If somebody asked me how to burn CDs in Linux, I'd tell him/her to RTFM
On the other hand, I'd help the user learn to formulate a query: "Go to Google.com, enter [ linux burn cd ], and click Google Search." Or, if a question is answered in the FAQ: "Look in the DJGPP FAQ, section 8.3."
Re:'RTFM' is more polite when you name a chapter (Score:2)
Maybe they don't know there are such things as search engines yet, maybe what they really need help with finding that information out, perhaps along with the answer to their original question you could explain search engines, I'm sure they would really appreciate that.
People often have different reasons, they may just have a different knowledge set than you. They may not be as intelligent, and where you were able to interpret the information you found during a google search easily, they need someone to translate it into something a little more user friendly before they will understand it. Perhaps as I said earlier, they are frustrated and need a simple answer before they can move back to tackling their real issue.
I don't know about you, but I work in a tech shop, all day long we ask each other questions, a great deal of them simple, it's only when someone else isn't available or the others don't know that you resort to a web search that takes more time. I'll evaluate how important it was for you to spend 5 minutes to answer a question I would have had to spend 2hrs figuring out on my own when you need to know something that I have experience with and could answer in 5mins and will save you 12...
Volunteers can do whatever they wish, be as friendly or not friendly as they wish, they can cater to whatever technical degree they wish on a given subject... but they certainly have no reason to flame those who have simpler questions, if you tired of it, or would rather help with more difficult things, so be it but that's an excuse for not answering it's no excuse for "RTFM".
I will say this though, I've spent a great deal of time on help channels.. both giving and recieving information. One, if you give information where you can, your more likely to get the information you need without a hassle. And two, if you tried to find the information and couldn't, someone will usually point you to it, even if they do so in the form of a flame. And three, if you did find the information, are bright enough to mention what you weren't clear on, someone will usually phrase it in another way or otherwise clarify even if it is in a exclamation that ends in "you fucking n00b".
Re:Speaking of which.. (Score:2)
What? I figure we're off-topic enough already as it is
Though it does bring up an interesting point that some people really just need to know where a manual is, or if one exists. Manpages often tell everything you could ask for regaurding command line switches, but doesnt talk at all about the interface, or even what it is the program does. The most helpful source of information could be burried in a seemingly unrelated HOWTO which you'd never know to search for without knowing the program's intended function in the first place [you just found it in some error report from cron]
I get the feeling that a lot of people who say "RTFM" havent actually read the specific manual in question, they've learned from others, and through experience with related things. I hate being told to RTFM after I just went through the entire thing and have found nothing even related to my problem.
Re:vs RTFM (Score:2)
man and info both support searching (with the / key in both, i believe)
most of the documentation for linux/unix that is not in man or info pages is in html, and most web browsers also support searching, although the key may vary
Re:Uhh (Score:2, Insightful)
When you *do* RTFM, not only do you get better at manual reading, but you also pick up additional information, so you may be less clueless the next time you have a problem
-BP
Re:Uhh (Score:1)
I'm trying to give a little perspective to the issue once a question has been accepted. Flaming the person who asked doens't do any good.
Re:Uhh (Score:1)
Your right, I had *meant* to flame (bit harsh of a word I think) Lord Bitman, but I got sloppy with the mouse. My apologies.
Re:Uhh (Score:1)
Re:Uhh (Score:1)
Space (Score:4, Informative)
Typically, there's a utility in the RAID configuration that stamps the drive as part of a set, marks the state (good, bad, rebuilding or hot-spare are most common) and some kind of versionig information.
I've ripped a few disks out of the array, mounted them as standard, reformatted and replaced the MBR, threw them back in the array, and still had them recognized as part of the RAID volume. The RAID card didn't like this much, however. :)
I think your best bet is to talk to one of the people who actually wrote the drivers for the card (you've got the Linux source, right :) or possibly see if you can get ahold of an engineer at the manufacturer and discuss ways of getting the information back.
Good luck!
Google.... (Score:2, Informative)
"Where does the controller store its configuration? Disk, Ram, Rom ? Can it be saved or exported as a backup?
The config is in NVRAM on the controller, but there's also about a 4MB
"partition" (not really a partition, but config area) on each drive in the
array that stores information on things like position in the array, etc.
Alternately, try this link [makeashorterlink.com] for the whole thread on the subject.
It literally took me 30 seconds to find it. Next time, try Google before posting, mmkay?
What query? (Score:1)
I went to Google and found this ... It literally took me 30 seconds to find it.
Next time, if you're reporting a Google result, please give the query string that you used. This way, people who read your comment become better users of the Google search engine.
Re:What query? (Score:1)
I put it into makeashorterlink by habit.
Re:Google.... (Score:1)
Nor did I. Is that the best you can do, little boy?
I think you're a stuck up, ego inflated, piece of shit who gets hard on being assholes to people asking legit questions on
Let me reiterate: "That's right. I'm superior. The sooner you realize that, the better things will be." Your jealousy is pathetic.
Tell your mom I'll be over later.
Re:Google.... (Score:1)
As for my handle. The whole point (which you OBVIOUSLY didn't get) was that, while anonymous, I at least have the spine to post under the account I signed up with. You, however, haven't had your testicles decend yet which is why you're posting under AC.
As for your mom -- I'll give her a break. Your father is much better at giving head anyway.
How's your wife and my kids, by the way?
Highpoint RAID hardware != Open Source software. (Score:1, Troll)
Re:Highpoint RAID hardware != Open Source software (Score:2)
Re:Highpoint RAID hardware != Open Source software (Score:1)
This is your third post in this thread that has nothing to do with answering the question (deemed too simple to be worthy of your time) but rather with the proper way of responding to the question, how the question is lame, etc.
Yeah, I'm just adding to that pile - but you're killing the hostages so that they're not killed by the kidnappers in an attempt to "save" em, here.
~~~~
Anyway, here's the proper way of not cluttering up slashdot (gee whiz, isn't it up to those accepting the questions to decide that?):
The answer is: there is some info regarding the drive partitions in the MBR, but most likely this information is stored on your controller itself in what's known as NVRAM.
Besides, I'd ask Jeeves but Jeeves prefers the term "jovial"
Depends (Score:4, Informative)
Hardware controllers generally reserve a small slice of disk to store configuration data. Sometimes this slice is marked unusable and can only be accessed by low-level hardware.
One of the big, unadvertised problems with RAID, particularly with new/buggy controllers, is that a controller failure can trash your data.
Unless you have the time & knowledge to reconstruct the data structures, a controller failure that screws up the configuration data on disk effectively destroys your data.
I recently had a HighPoint controller fail (Score:2)
Unless I misunderstand - your system *is* broken without the controller anyways right? So why not just replace it?
Re:I recently had a HighPoint controller fail (Score:2)
Actually, I'm from Oregon. Regardless of the impression my text gives, I can speak English rather fluently. When sober anyways.
Re:I recently had a HighPoint controller fail (Score:1)
In other words: Get another HighPoint controller, reconfigure it the same way the old one was, and see if it works. If it doesn't, you are most likely screwed and will need to restore from backup. Good luck.
Call tech support. (Score:1, Interesting)
You can reach the web page at highpoint-tech.com [highpoint-tech.com], and reach support via support@highpoint-tech.com [mailto]
Good luck to you, but ask your question in a support fourum.
Ask Highpoint (Score:4, Informative)
You'll need to do something like this, since you won't be able to get at the data on the drives unless you can hook them up to a RAID controller that will recognize the particular flare code etc of your setup.
If you can stomach losing the data (you backed up the important stuff, right?) then you could try starting over from scratch, but I would not trust your RAID controller if I were you. Replace it or don't use it.
A bit of info (Score:4, Informative)
AMI Megaraid(and now LSI) write a bit of config info to each disk and to the controller. On these cards, you need to know the drive designations (which is drive1, which is drive 2, etc and the stripe size (how much data to write to the first disk before moving on to the second). On these controllers, if your card goes belly up you can usually put in a new card which will detect that your drives still have a configuration and use it. Otherwise, you can create a new configuration of the drives (same raid level, same stripe size, each drive with same designation) and it will access the data just fine on a reboot. (probably 75-85% of the time. The rest of the time you are just SOL and need to get out tape.)
Adaptec's ZCR card we were testing and going to ship had the unfortunate effect that when an array was created, it immediately initialized (format) all the data.
This is something you should check into. Perhaps the highpoint card will let you make a new array and reboot. Or it might automatically initialize and wipe out all your data before letting you use it.
Hope this helps
RTFS :-) (Score:2)
I had a very similar thing happen to me a while back. It was caused by a hardware problem (I was using a pair of IBM deskstar drives), so I never did recover quite all the data, but I did manage to get the RAID array back together. By a lucky coincidence, this happened shortly after drivers/ide/hptraid.h was added to the linux kernel, so I had somewhere to look for inspiration.
This file describes the structure of one sector somewhere near the start of each disk. (Sorry, I don't remember exactly which one.) The magic number had changed on one of the disks from HPT_MAGIC_OK to HPT_MAGIC_BAD. Editing it back again was sufficient to reconnect the drives.
Usually easy to fix on most controllers I've seen (Score:1)
Is this Highpoint? (Score:1)
Simple. (Score:1)
Voila! Complete Recovery in less time than it took for all these responses to be posted.
No backup? Ewww - you are going to hate Monday.
The Fix: (Score:2)
1) Backup the drives manually just in case (copy the raw drive data off to tape after booting from CD or floppy).
2) Go into the hardware raid setup and set the array up exactl as before, but dont let it initialize. If your hardware raid controller always initializes new divces by writing over them with zeros or something, this might be undoable or tricky. If you end up initializing, it's not that big a deal.
3) If you did it without initializing, you're probably good to go. If you ahd to initialize in order to configure the array, now boto off of CD again and restore the raw drive images from tape.
Done
An answer and a proposed solution (Score:1)
Solution:
1. Backup everything.
2. Copy (dd, ghost) the most current drive to the least current drive.
3. Go into the Highpoint BIOS config and re-declare the drives as a RAID-0.
4. At this point the Highpoint BIOS will probably try to initialize the RAID-0. Since you copied the drives using a sector copy program in step 2, the direction of the Highpoint initialization doesn't matter.
5. If this worked, weverything will boot normally with the RAID-0 config.
6. If this didn't work, the drives are probably irrepairably hosed. Restore from the backup you made in Step 1. You did make a backup in Step 1, right?
Good Luck,
Ed
Same Thing Happened To Me - Simple Solution (Score:1)
YMMV, but good luck.
Someone alert the Free Software Foundation (Score:1)
Someone alert the FSF! You're clearly insane! The software industry's brainwashed you, and you need help!
The Real Question (Score:2)
RAID behavior (Score:2)
Infact, I have a Compaq Smart array SCSI RAID controller in both my PC's at home (desktop and server). They're available on ebay for very nice prices and are well supported by Linux.
The reason I mention it, is that I can pull all the disks out from one machine and pop them into the other - I don't even have to keep them in the same order! - and the controller is able to read the array configuration data from the disks and the logical volume(s) are immediately accessible. It's pretty sweet.
If it's just your RAID controller that's failed, try putting the disks into another machine with the same type of controller, or try replacing the controller. I'm not making any promises, but if it's a decent controller it should read the saved config data from the disks and make your logical volume available.
Have you tried the manufacturers tech support line? I'm sure they've delt with this situation before. I'm not trying to be a wiseass, but sometimes contacting the manufacturer is going to get you in touch with the folks who are most knowlegable about the product.
Maybe you have too much time on your hands (Score:1)