Question regarding wii nand

I'm used to nand backups on my psp . On the psp over time the nand picks up new bad blocks. This brings about a risk of making existing nand backups useless. Obviously the recovery application would try to write to the memory addresses of the new bad blocks. Therefore the brick isn't repaired and you have no backup which will work anymore.

My question is how susceptible to nand degradation is the wii? Its not being moved around as much as say a psp removing risks from damage through physical stresses. Could a method of checking the compatibility of a dump with the current state of the wii nand be integrated into BootMii?

Also I understand how a nand dump can't be moved from one wii to another; the same is true on the psp, because of the unique keys in each wii. If the worst happened and you had no backup for your nand, would with current knowledge a method of generating a new nand structure be possible? The unique keys obviously play a role in there generation, if like the psp, its just a matter of working out how and making a program to do this and integrate it within bootmii.

If this is just total conjecture on my part please ignore and delete. Admittedly i have little understanding of the internal workings and mechanics of the wii.



Edited 1 time(s). Last edit at 05/14/2009 11:00PM by niko86.

Great question. I'm assuming the chances of the bad blocks being the location of what is causing the brick will be slim to none, so even if it can't write to that area, it should still recover the Wii.

Also assuming NAND degradation is the same with any product...different with each and every NAND.

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diffikolt
Great question. I'm assuming the chances of the bad blocks being the location of what is causing the brick will be slim to none, so even if it can't write to that area, it should still recover the Wii.

Also assuming NAND degradation is the same with any product...different with each and every NAND.

I don't think you totally get what i mean. I know all nands won't degrade in the same way.

Say I have a nand backup with 0 bad blocks. As an example block 1 goes bad and it held a vital system file. You go to restore your nand backup for whatever reason, now is the restoration process intelligent? Would it rearrange the backup to take into account this new bad block, or just try and write to that block? Thus making your backup useless.

Therefore when i mention is it possible to make a program to check the backup, compare its structure to that of your wii's current nand state to see if they are compatible. And as a further thought if there is a discrepency between the two could the program modify the backup to compensate for changes in the nand since the backup was taken?

No, it can't intelligently move stuff around. Right now, if you try to restore a dump from one flash chip to another and the new chip has a bad block where the old chip stored a vital file, you're screwed.

Most of the time, the bad blocks will fall in unimportant files, and when you boot, IOS can try to move around the data. Sometimes you're left with a system that can't boot. (It's rate, but I've seen it happen 2-3 times out of about 10-15 tries).

Moving the data around inside mini requires implementing a read-write driver for the NAND FS, which is doable but not easy.

Generation of a new nand file structure within the wii something thats ever been looked into? I'd guess its probably all down to working out how nintendo generates them on an individual basis using each machine individual keys.

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niko86

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diffikolt
Great question. I'm assuming the chances of the bad blocks being the location of what is causing the brick will be slim to none, so even if it can't write to that area, it should still recover the Wii.

Also assuming NAND degradation is the same with any product...different with each and every NAND.

I don't think you totally get what i mean. I know all nands won't degrade in the same way.

Say I have a nand backup with 0 bad blocks. As an example block 1 goes bad and it held a vital system file. You go to restore your nand backup for whatever reason, now is the restoration process intelligent? Would it rearrange the backup to take into account this new bad block, or just try and write to that block? Thus making your backup useless.

Therefore when i mention is it possible to make a program to check the backup, compare its structure to that of your wii's current nand state to see if they are compatible. And as a further thought if there is a discrepency between the two could the program modify the backup to compensate for changes in the nand since the backup was taken?

I understood what you were saying, hence me saying "It should still recover the Wii."

However, if there was a bad block located where a VITAL file was located, wouldn't your Wii not load regardless?

So what I meant was, chances are, the restore would work fine.

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diffikolt
However, if there was a bad block located where a VITAL file was located, wouldn't your Wii not load regardless?

I see what you mean with your original reply.

Yet if you had an old nand backup. Then a bad block appears corrupting a vital file you would assume you could restore the brick with the nand backup.But you can because the file that was damaged cant be restored to where the backup says it should go.

TBH i'm rubbish at explaining, its a wonder anyone understands my rambles ;p

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niko86
Generation of a new nand file structure within the wii something thats ever been looked into? I'd guess its probably all down to working out how nintendo generates them on an individual basis using each machine individual keys.

What we would need here, methinks, is just backup of the keys. Then use some MINI-using Any Region Changer-clone that: (1) Wipes the Wii, (2) Injects the new key info into the right places, (3) Reinstalls System Menu and all IOS:es from Nintendos servers.

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magu
What we would need here, methinks, is just backup of the keys. Then use some MINI-using Any Region Changer-clone that: (1) Wipes the Wii, (2) Injects the new key info into the right places, (3) Reinstalls System Menu and all IOS:es from Nintendos servers.

If this would work it would save the inevitable cries of people who lose nand backups etc and no way to recover.

I guess it would be possible to restore wii's to something close to their original configurations when bought. Making removing a few months of uneducated installations and modifications alot easier ;p

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niko86

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magu
What we would need here, methinks, is just backup of the keys. Then use some MINI-using Any Region Changer-clone that: (1) Wipes the Wii, (2) Injects the new key info into the right places, (3) Reinstalls System Menu and all IOS:es from Nintendos servers.

If this would work it would save the inevitable cries of people who lose nand backups etc and no way to recover.

I guess it would be possible to restore wii's to something close to their original configurations when bought. Making removing a few months of uneducated installations and modifications alot easier ;p

Problem though with this is that it'd make it really easy to spoof your Wii keys, which would possibly induce problems, since those are supposed to be unique.

Best, restore wise of course, would be to have an BootMii/MINI run-able installer where you manually enter all keys, and then *poof* *WHAM* ... Wipe nand and download all IOS:es + System Menu from Nintendo's server .... *BANG* *whack* ... virgin vanilla 4.0E Wii with those particular NAND and SD-keys.

But, as mentioned before, I doubt the Twiizers want to go this path.