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#1
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Hard drive experiments
Now that I'm an old retired guy I am finally getting around to doing a
few things I've always wanted to try concerning hard drives. I mentioned in another thread that I had two drives taken out by a PSU that failed. I had all data backed up but wanted to see if switching out the controller board might make the drives usable. They were both WD 500G drives but I really did not want to buy one or two more just for the sake of experimenting. I do have a WD 320 drive with a controller that has the same part number on it but was not sure if that would work. As it turns out I found a WD 80G drive and a WD 120 gig drive that have the same controller number and I swapped them...and each worked! So I figured the controller from the 320G drive might work in the 500G It did not however. That leads me to beleive that more has failed on the drive than the controller board. |
#2
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Hard drive experiments
philo wrote:
Now that I'm an old retired guy I am finally getting around to doing a few things I've always wanted to try concerning hard drives. I mentioned in another thread that I had two drives taken out by a PSU that failed. I had all data backed up but wanted to see if switching out the controller board might make the drives usable. They were both WD 500G drives but I really did not want to buy one or two more just for the sake of experimenting. I do have a WD 320 drive with a controller that has the same part number on it but was not sure if that would work. As it turns out I found a WD 80G drive and a WD 120 gig drive that have the same controller number and I swapped them...and each worked! So I figured the controller from the 320G drive might work in the 500G It did not however. That leads me to beleive that more has failed on the drive than the controller board. The two drives just might use different density platters. Sometimes, one drive is just a platter more than another drive, and the controller board runs 1,2,3, or 4 platters. That might make a good swap. But say the 320 was a 1x320 and the 500 was a 2x250. The metadata in the service area on the two might be different. There are also some exceptional cases. WDC didn't want to make any more 500GB drives. They took some 1TB drives and "short-stroked" them in firmware. That means they certify the whole 1TB surface, but to give the customer exactly what they purchased, the heads only go from outer diameter to center diameter. Never touching the hub. Both drives have the same part number. Now, imagine you need to do a controller swap. The controllers are different. Quite different. I think I might own three of those, two ordinary, and one short stroked. I've also seen a claim in a hard drive repair forum, that some controllers are "branded", and if you swap controllers, you have to transfer a small ROM from one controller to the other. Whether this is FDE in disguise, I don't know. There was a claim at one time, that all drives would be Full Disk Encryption by year X, and when that year arrived we heard... nothing. Crickets. But that doesn't mean a drive can't be FDE and use a private key. The owner is oblivious to the danger, until the private key (on the controller) is lost. Transferring the controller affords a way to lose it. The key method is attractive, as on such drives, if you do a Secure Erase, instead of taking two hours and writing the entire surface, the controller just erases the private key, *instantly* rendering all the data on the disk as gibberish. It looks like solid binary after that. Because without the key, the contents are just "scrambled eggs". Playing with hard drives is full of "what ifs". Paul |
#3
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Hard drive experiments
On 7/8/2019 9:25 PM, Paul wrote:
philo wrote: Now that I'm an old retired guy I am finally getting around to doing a few things I've always wanted to try concerning hard drives. I mentioned in another thread that I had two drives taken out by a PSU that failed. I had all data backed up but wanted to see if switching out the controller board might make the drives usable. They were both WD 500G drives but I really did not want to buy one or two more just for the sake of experimenting. I do have a WD 320 drive with a controller that has the same part number on it but was not sure if that would work. As it turns out I found a WD 80G drive and a WD 120 gig drive that have the same controller number and I swapped them...and each worked! So I figured the controller from the 320G drive might work in the 500G It did not however. That leads me to beleive that more has failed on the drive than the controller board. The two drives just might use different density platters. Sometimes, one drive is just a platter more than another drive, and the controller board runs 1,2,3, or 4 platters. That might make a good swap. But say the 320 was a 1x320 and the 500 was a 2x250. The metadata in the service area on the two might be different. There are also some exceptional cases. WDC didn't want to make any more 500GB drives. They took some 1TB drives and "short-stroked" them in firmware. That means they certify the whole 1TB surface, but to give the customer exactly what they purchased, the heads only go from outer diameter to center diameter. Never touching the hub. Both drives have the same part number. Now, imagine you need to do a controller swap. The controllers are different. Quite different. I think I might own three of those, two ordinary, and one short stroked. I've also seen a claim in a hard drive repair forum, that some controllers are "branded", and if you swap controllers, you have to transfer a small ROM from one controller to the other. Whether this is FDE in disguise, I don't know. There was a claim at one time, that all drives would be Full Disk Encryption by year X, and when that year arrived we heard... nothing. Crickets. But that doesn't mean a drive can't be FDE and use a private key. The owner is oblivious to the danger, until the private key (on the controller) is lost. Transferring the controller affords a way to lose it. The key method is attractive, as on such drives, if you do a Secure Erase, instead of taking two hours and writing the entire surface, the controller just erases the private key, *instantly* rendering all the data on the disk as gibberish. It looks like solid binary after that. Because without the key, the contents are just "scrambled eggs". Playing with hard drives is full of "what ifs". ** Paul Well, I'm just playing that's all. I was in the industrial battery business and know how labeling goes. At one time a lower ampere-hour battery and changer was sometimes identical to the next size up...other than the name plate. |
#4
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Hard drive experiments
On 7/10/2019 10:22 AM, philo wrote:
On 7/8/2019 9:25 PM, Paul wrote: philo wrote: Now that I'm an old retired guy I am finally getting around to doing a few things I've always wanted to try concerning hard drives. I mentioned in another thread that I had two drives taken out by a PSU that failed. I had all data backed up but wanted to see if switching out the controller board might make the drives usable. They were both WD 500G drives but I really did not want to buy one or two more just for the sake of experimenting. I do have a WD 320 drive with a controller that has the same part number on it but was not sure if that would work. As it turns out I found a WD 80G drive and a WD 120 gig drive that have the same controller number and I swapped them...and each worked! So I figured the controller from the 320G drive might work in the 500G It did not however. That leads me to beleive that more has failed on the drive than the controller board. The two drives just might use different density platters. Sometimes, one drive is just a platter more than another drive, and the controller board runs 1,2,3, or 4 platters. That might make a good swap. But say the 320 was a 1x320 and the 500 was a 2x250. The metadata in the service area on the two might be different. There are also some exceptional cases. WDC didn't want to make any more 500GB drives. They took some 1TB drives and "short-stroked" them in firmware. That means they certify the whole 1TB surface, but to give the customer exactly what they purchased, the heads only go from outer diameter to center diameter. Never touching the hub. Both drives have the same part number. Now, imagine you need to do a controller swap. The controllers are different. Quite different. I think I might own three of those, two ordinary, and one short stroked. I've also seen a claim in a hard drive repair forum, that some controllers are "branded", and if you swap controllers, you have to transfer a small ROM from one controller to the other. Whether this is FDE in disguise, I don't know. There was a claim at one time, that all drives would be Full Disk Encryption by year X, and when that year arrived we heard... nothing. Crickets. But that doesn't mean a drive can't be FDE and use a private key. The owner is oblivious to the danger, until the private key (on the controller) is lost. Transferring the controller affords a way to lose it. The key method is attractive, as on such drives, if you do a Secure Erase, instead of taking two hours and writing the entire surface, the controller just erases the private key, *instantly* rendering all the data on the disk as gibberish. It looks like solid binary after that. Because without the key, the contents are just "scrambled eggs". Playing with hard drives is full of "what ifs". Â*Â*Â* Paul Well, I'm just playing that's all. I was in the industrial battery business and know how labeling goes. At one time a lower ampere-hour battery and changer was sometimes identical to the next size up...other than the name plate. Yeah. Identical products with different part numbers and a range of prices -- all because some had longer warranty periods covered by the higher cost. |
#5
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Hard drive experiments
On 7/10/19 9:54 AM, John McGaw wrote:
On 7/10/2019 10:22 AM, philo wrote: On 7/8/2019 9:25 PM, Paul wrote: philo wrote: Now that I'm an old retired guy I am finally getting around to doing a few things I've always wanted to try concerning hard drives. I mentioned in another thread that I had two drives taken out by a PSU that failed. I had all data backed up but wanted to see if switching out the controller board might make the drives usable. They were both WD 500G drives but I really did not want to buy one or two more just for the sake of experimenting. I do have a WD 320 drive with a controller that has the same part number on it but was not sure if that would work. As it turns out I found a WD 80G drive and a WD 120 gig drive that have the same controller number and I swapped them...and each worked! So I figured the controller from the 320G drive might work in the 500G It did not however. That leads me to beleive that more has failed on the drive than the controller board. The two drives just might use different density platters. Sometimes, one drive is just a platter more than another drive, and the controller board runs 1,2,3, or 4 platters. That might make a good swap. But say the 320 was a 1x320 and the 500 was a 2x250. The metadata in the service area on the two might be different. There are also some exceptional cases. WDC didn't want to make any more 500GB drives. They took some 1TB drives and "short-stroked" them in firmware. That means they certify the whole 1TB surface, but to give the customer exactly what they purchased, the heads only go from outer diameter to center diameter. Never touching the hub. Both drives have the same part number. Now, imagine you need to do a controller swap. The controllers are different. Quite different. I think I might own three of those, two ordinary, and one short stroked. I've also seen a claim in a hard drive repair forum, that some controllers are "branded", and if you swap controllers, you have to transfer a small ROM from one controller to the other. Whether this is FDE in disguise, I don't know. There was a claim at one time, that all drives would be Full Disk Encryption by year X, and when that year arrived we heard... nothing. Crickets. But that doesn't mean a drive can't be FDE and use a private key. The owner is oblivious to the danger, until the private key (on the controller) is lost. Transferring the controller affords a way to lose it. The key method is attractive, as on such drives, if you do a Secure Erase, instead of taking two hours and writing the entire surface, the controller just erases the private key, *instantly* rendering all the data on the disk as gibberish. It looks like solid binary after that. Because without the key, the contents are just "scrambled eggs". Playing with hard drives is full of "what ifs". Â*Â*Â* Paul Well, I'm just playing that's all. I was in the industrial battery business and know how labeling goes. At one time a lower ampere-hour battery and changer was sometimes identical to the next size up...other than the name plate. Yeah. Identical products with different part numbers and a range of prices -- all because some had longer warranty periods covered by the higher cost. Yes. Now after I've been retired I see the logic. |
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