Merged: Questions about NAND backup format

[note: I'm merging several threads into one, for the sake of convenience - bushing]

I'm new to this forum so let me start by congratulating the bootmii team for their success. Anyway, does anyone know if bootmii will restore from other NAND software such as YAWND (or other software like it)? I haven't modified my Wii yet and am hoping someone else knows.

Assuming that YAWND does work, I was thinking I might be able to use bannerbomb to get a backup of my clean Wii before installing anything. Then I'd like to put boot2 bootmii on it and take another backup (one that I know works with bootmii). I do wonder though if I took the original, clean YAWND backup and used that in bootmii, would there be a problem (I would be wiping bootmii out of the NAND as well)? I'm not really planning on doing that since it kind of defeats the purpose of bootmii but it is always nice to know that such a regression would work if needed. Any thoughts?



Edited 1 time(s). Last edit at 06/09/2009 02:56PM by bushing.

Hi folks!

Just a little question: can I restore a Nand Backup made with RealWnd? And one made with other dumper?

Thanks in advance!



Edited 1 time(s). Last edit at 06/03/2009 05:23PM by lolololailo.

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music_guru
[note: I'm merging several threads into one, for the sake of convenience - bushing]
I'm new to this forum so let me start by congratulating the bootmii team for their success. Anyway, does anyone know if bootmii will restore from other NAND software such as YAWND (or other software like it)? I haven't modified my Wii yet and am hoping someone else knows.

Almost. BootMii adds a 1024-byte footer to the end of the NAND dump that contains your console ID and the contents of OTP and SEEPROM. When you go to restore, it will check that console ID against your console ID, and refuse to restore if they don't match (as a safety measure). The format is straightforward; just look at a dump.

You could make a backup with BootMii, take the footer from that backup and tack it onto the end of another NAND dump, assuming that dump includes the ECC data (so you would be turning a 553,648,128 byte file into a 553,649,152 byte file). However, I don't think this is what you're getting at -- read further:

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Assuming that YAWND does work, I was thinking I might be able to use bannerbomb to get a backup of my clean Wii before installing anything. Then I'd like to put boot2 bootmii on it and take another backup (one that I know works with bootmii). I do wonder though if I took the original, clean YAWND backup and used that in bootmii, would there be a problem (I would be wiping bootmii out of the NAND as well)? I'm not really planning on doing that since it kind of defeats the purpose of bootmii but it is always nice to know that such a regression would work if needed. Any thoughts?

No matter what backup you restore with BootMii, it will refuse to overwrite itself (or boot1 or boot2) as a safety precaution. That way, even if something goes wrong with a restore, you should still be left with a system that can at least boot into BootMii, and you can try again.

No data is overwritten when BootMii is installed into boot2; it's installed over two otherwise-empty blocks, and can be removed by simply erasing those two blocks. Backing up before and after installing BootMii won't really buy you much; if something WERE to go wrong with BootMii, you'd have a rather difficult time flashing your pre-BootMii dump back onto your system.

Thanks for the post bushing - great info! Basically that reassures me that I don't necessarily need to mess around with another NAND backup tool (although RealWnP's development seems interesting). However, in relation to lolololailo's question, I did come across a utility that seems to convert NAND images (NI2NP.exe from http://www.wiibrew.org/wiki/User:Pcfree/RealWnP). Truthfully, I'm not entirely sure what this does, but I'll quote the info here:

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NI2NP.exe is a Win32 command line tool to convert your old NAND Image to NAND packed image set with date/time as Pack Name or user-defined Pack Name. The pack image set should be manually copied to RealWnS directory in SD card for using by RealWnW. The old NAND image may come from +ECC dump of RealWnD, YaWnD, WiiND or even NAND.BIN from BootMii.

Maybe this info combined with the format information bushing provied might be useful to people who have older backups before bootmii was around. But at this stage, bootmii seems to be the real best option for backups currently.

EDIT: Looks like NI2NP specifically focuses on converting a normal NAND image into a packed image (as it states above) and probably limits its use to RealWnW. Assuming you even have the beta, pcfree still suggests using bootmii to recover from any major problems.



Edited 1 time(s). Last edit at 06/09/2009 11:08PM by music_guru.

When Bootmii does a nand dump, does it skip dumping boot2 as part of the "save time" process?
What I'm getting to here is can I take the first 8 blocks from a nand dump made with Bootmii and flash it using a nand programmer?

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Cappo
When Bootmii does a nand dump, does it skip dumping boot2 as part of the "save time" process?
What I'm getting to here is can I take the first 8 blocks from a nand dump made with Bootmii and flash it using a nand programmer?

It backups everything, so taking the first 8 blocks from a dump should work ok.

BootMii only skips part of NAND while restoring; and that's because it, as mentioned before, only overwrites diff:ing blocks.

Ok, thanks

To prevent user imporperly append good footer to some kind of bad image, I suggest it might be necessary to verify the image body. For example, verify one cluster of HMAC signature in SFFS area with OTP HMAC key.

Nah, if a user wants to deliberately move a footer from one image to another, that's fine. I'm only trying to prevent accidents.