Homebrew How to downgrade to 2.1 to re-dump otp AFTER installing a9lh

[TheCyberQuake]

So a week ago I installed a9lh to my sister's 3ds. Unfortunately I did it late at night and forgot to save the otp.bin to my computer and google drive before deleting it from her SD card. What would be the best way to downgrade back to 2.1 and dump the otp again?

 

[evandixon]

So a week ago I installed a9lh to my sister's 3ds. Unfortunately I did it late at night and forgot to save the otp.bin to my computer and google drive before deleting it from her SD card. What would be the best way to downgrade back to 2.1 and dump the otp again?

Do you need the OTP? IIRC you don't need it to change payloads.

 

[SomeGamer]

So a week ago I installed a9lh to my sister's 3ds. Unfortunately I did it late at night and forgot to save the otp.bin to my computer and google drive before deleting it from her SD card. What would be the best way to downgrade back to 2.1 and dump the otp again?

Restore a pre-A9LH NAND backup, then start the process over.

 

[TheCyberQuake]

Do you need the OTP? IIRC you don't need it to change payloads.

No I don't NEED it, and I know I can update payloads without it. I would just like to have it in case anything new can be done with it in the future.

Restore a pre-A9LH NAND backup, then start the process over.

Is there any reason I can't just downgrade directly?
Edit: I just remembered no CFW can run 2.1, thus I can't do that

 

[uyjulian]

No I don't NEED it, and I know I can update payloads without it. I would just like to have it in case anything new can be done with it in the future.


Is there any reason I can't just downgrade directly?
Edit: I just remembered no CFW can run 2.1, thus I can't do that

You want your NAND? Back up your nand first then flash your pre-a9lh backup. After you are all done, flash your nand you got in the first step.

 

[EmperorOfCanada]

any chance you can just use a data recovery tool on your computer and find the deleted SD backup?

 

[TheCyberQuake]

any chance you can just use a data recovery tool on your computer and find the deleted SD backup?

I actually thought about doing that, but didn't want to risk having some of it partially corrupted without me realizing it. I may give it a try though, just to see. I'm highly doubtful but who knows.

 

[zoogie]

I actually thought about doing that, but didn't want to risk having some of it partially corrupted without me realizing it. I may give it a try though, just to see. I'm highly doubtful but who knows.

Is this a new3ds by any chance? I think you can dump the otp from a a9lh'd new3ds. Or at least the sha256 of the otp which is the important part.

 

[TheCyberQuake]

Is this a new3ds by any chance? I think you can dump the otp from a a9lh'd new3ds. Or at least the sha256 of the otp which is the important part.

Nope, o3ds.

 

[Seriel]

You literally will never need the otp again so there's not much point.

 

[TheCyberQuake]

You literally will never need the otp again so there's not much point.

I was only going to try to get it if there was an easy way. But there isn't. Worst case if something ever were to be released that also uses a dumped otp.bin (which I doubt anything will) I could just restore a non-a9lh 9.2 sysNAND and go from there. I would even have a formatted redNAND backup I could use. It honestly wouldn't take that long to get, but I'm lazy and it isn't necessary at this time.