Hacking Question Restore clean sysNAND and preparing for emuEMMC

[Darkrai27]

I have a clean NAND backup from when my switch was completely clean, I think that was 4.0.1, how can I verify it? Now I'm in 6.X, updated through ChoiDojour to add exFAT support. Any guide or thread of how to downgrade again and restore that backup properly? I suppose that my backup is partitioned, because in 4.0.1 switch only supported FAT32 for the sdcard.

Thanks

 

[Kafluke]

Do you have boot0 and boot1 also? Did you turn on autoRCM? How many fuses are burnt?

 

[Trekker]

If you have boot0/1 and either rawnand or SYS and USER, then you don't need to downgrade just restore your NAND.

However did you install AutoRCM before doing that NAND backup?

 

[Darkrai27]

If you have boot0/1 and either rawnand or SYS and USER, then you don't need to downgrade just restore your NAND.

However did you install AutoRCM before doing that NAND backup?

I have BOOT0,BOOT1 and rawnand splited in 14 parts. And no, I installed AutoRCM after doing the backup

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Do you have boot0 and boot1 also? Did you turn on autoRCM? How many fuses are burnt?

Yes, I suppose that the same ones than when my NAND was clean, I've been always with autorcm after updating with choidojour, how can I chack it?

 

[Kafluke]

I have BOOT0,BOOT1 and rawnand splited in 14 parts. And no, I installed AutoRCM after doing the backup

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Yes, I suppose that the same ones than when my NAND was clean, I've been always with autorcm after updating with choidojour, how can I chack it?

Launch hekate and select print fuses.

 

[Shadow LAG]

I had a rawnand backup without boot0/1 a few days ago and did exactly what you are wanting to do here.

Identified the version of my rawnand backup using this https://gbatemp.net/threads/firmware-version-inspector-get-fw-version-from-nand-dump.515308/

Performed a new backup of rawnand and boot0/1 in case I needed it.

Downgraded from 8.0.1 to the 4.0.1 using ChoiDojourNX and 4.0.1 update files + factory reset.

Restored 4.0.1 rawnand immediately since new boot0/1 4.0.1 binaries were generated.

Booted in once to sysnand for the first time since rawnand restore and performed update. Only problem is 8.1.0 does not support autoRCM now, so if you are wanting that hold off updating through nintendo servers.

 

[Trekker]

You can merge your rawnand parts with the "copy /b" command in CMD. You'll need a exfat formatted SD card though.

 

[Slim45]

I had a rawnand backup without boot0/1 a few days ago and did exactly what you are wanting to do here.

Identified the version of my rawnand backup using this https://gbatemp.net/threads/firmware-version-inspector-get-fw-version-from-nand-dump.515308/

Performed a new backup of rawnand and boot0/1 in case I needed it.

Downgraded from 8.0.1 to the 4.0.1 using ChoiDojourNX and 4.0.1 update files + factory reset.

Restored 4.0.1 rawnand immediately since new boot0/1 4.0.1 binaries were generated.

Booted in once to sysnand for the first time since rawnand restore and performed update. Only problem is 8.1.0 does not support autoRCM now, so if you are wanting that hold off updating through nintendo servers.

wouldnt just restoring ure 4.1 rawnand boo0/1 do the trick?

 

[Darkrai27]

You can merge your rawnand parts with the "copy /b" command in CMD. You'll need a exfat formatted SD card though.

But I need to merge the parts of the rawnand or hekate does it automatically??

--------------------- MERGED ---------------------------

I had a rawnand backup without boot0/1 a few days ago and did exactly what you are wanting to do here.

Identified the version of my rawnand backup using this https://gbatemp.net/threads/firmware-version-inspector-get-fw-version-from-nand-dump.515308/

Performed a new backup of rawnand and boot0/1 in case I needed it.

Downgraded from 8.0.1 to the 4.0.1 using ChoiDojourNX and 4.0.1 update files + factory reset.

Restored 4.0.1 rawnand immediately since new boot0/1 4.0.1 binaries were generated.

Booted in once to sysnand for the first time since rawnand restore and performed update. Only problem is 8.1.0 does not support autoRCM now, so if you are wanting that hold off updating through nintendo servers.

Did you downgraded to 4.0.1 adding exFat support with ChoiDojour?? Or without exFat??

 

[Trekker]

But I need to merge the parts of the rawnand or hekate does it automatically??

--------------------- MERGED ---------------------------



Did you downgraded to 4.0.1 adding exFat support with ChoiDojour?? Or without exFat??

But why would you downgrade if you have Boot0/1 and rawnand?

You could try to restore with Rawnand parts, but i had trouble restoring USER parts so maybe you will have the same problem.

 

[Shadow LAG]

But I need to merge the parts of the rawnand or hekate does it automatically??

--------------------- MERGED ---------------------------



Did you downgraded to 4.0.1 adding exFat support with ChoiDojour?? Or without exFat??

You can use your existing BOOT0/1 backup files if you have them and skip the downgrade process altogether by restoring them. I was simply stating how I performed the procedure with rawnand only. Figured that would be useful to you if you had autorcm installed prior to dumping as it can modify your boot files. Hekate should be able to do it automatically. Just remember to make a backup of your existing BOOT0/1 and rawnand

P.S. I use EXFAT firmware with FAT32 formatted SD card.

 

[yoshimashi]

Do you have boot0 and boot1 also? Did you turn on autoRCM? How many fuses are burnt?

Is there any way to know if autoRCM was on at the time of backup? I want to do what the thread starter is doing also.. But I can't remember if it was on autorcm or not. I was just following the instructions that was posted sdswitch or something like that so if it didn't mention autorcm before the backup then I wouldn't have clicked on it because I didn't know what autorcm was back then either.

 

[Shadow LAG]

Is there any way to know if autoRCM was on at the time of backup? I want to do what the thread starter is doing also.. But I can't remember if it was on autorcm or not. I was just following the instructions that was posted sdswitch or something like that so if it didn't mention autorcm before the backup then I wouldn't have clicked on it because I didn't know what autorcm was back then either.

Then just do what I did.

 

[Darkrai27]

You can use your existing BOOT0/1 backup files if you have them and skip the downgrade process altogether by restoring them. I was simply stating how I performed the procedure with rawnand only. Figured that would be useful to you if you had autorcm installed prior to dumping as it can modify your boot files. Hekate should be able to do it automatically. Just remember to make a backup of your existing BOOT0/1 and rawnand

P.S. I use EXFAT firmware with FAT32 formatted SD card.

Ok, Thanks!

 

[Kafluke]

I still have not seen a report of OP's fuse count. It matters

 

[silentflames]

I still have not seen a report of OP's fuse count. It matters

I assume if too many fuses are already burnt it won't work?

 

[Slim45]

hekate ignores fuse count

 

[Kafluke]

hekate ignores fuse count

It's just a jumping off point. When troubleshooting switch problems I always like to know what the fuse count is and if possible the version of sysnand.

 

[Shadow LAG]

I assume if too many fuses are already burnt it won't work?

Fuse count is ignored by bootloader payloads such as hekate or sxos. Won't matter for the downgrade / restore at all as long as BOOT0/1 are for the same firmware version as your NAND image.