Resolved OCLP Monterey + Dosdude Mojave dual boot gone from boot picker

[pullman]

Hello

My cMP3,1 has Monterey installed via OCLP and also a Dosdude version of Mojave on another drive. Until today both appeared in the OCLP boot picker, but now there's only the Monterey option.

Can't think of anything that would have caused this except, possibly, that I tried to create an Apple Hardware Test bootable USB today. Earlier today I had had a "volume hash mismatch" error which I wanted to check out. In order to create the AHT USB I had to run (as adjusted):

cp -r /Volumes/AHT/System /Volumes/USBstick/
sudo bless --folder /Volumes/USBstick/ --file /Volumes/USBstick/System/Library/CoreServices/.diagnostics/diags.efi --label AHT

It seems a bit farfetched that this would have affected the boot menu, or? Having created the USB I tried booting from it but was not able to; I only got a black screen. So I powered down the machine and restarted. That's when I noticed that Mojave was gone from the boot picker.

I have tried setting the Mojave disk as Startup Disk in Sys Prefs, but that will just bring me to the OCLP boot picker with Monterey as the only alternative.

Any ideas how I can solve this?

Thanks very much in advance
Philip

 

[MrScratchHook]

Hello

My cMP3,1 has Monterey installed via OCLP and also a Dosdude version of Mojave on another drive. Until today both appeared in the OCLP boot picker, but now there's only the Monterey option.

Can't think of anything that would have caused this except, possibly, that I tried to create an Apple Hardware Test bootable USB today. Earlier today I had had a "volume hash mismatch" error which I wanted to check out. In order to create the AHT USB I had to run (as adjusted):


It seems a bit farfetched that this would have affected the boot menu, or? Having created the USB I tried booting from it but was not able to; I only got a black screen. So I powered down the machine and restarted. That's when I noticed that Mojave was gone from the boot picker.

I have tried setting the Mojave disk as Startup Disk in Sys Prefs, but that will just bring me to the OCLP boot picker with Monterey as the only alternative.

Any ideas how I can solve this?

Thanks very much in advance
Philip

remove monterey drive, do a pram reset and see what happens.

 

[pullman]

Thank you for replying, and apologies it took a while to reply, but I only recently managed to find time today to look into this.

I tried your suggestion and it did bring back the Mojave drive. Truly excellent, thank you.

In more detail what I did was:

1. Restore the clean Mojave install I had on another drive.
2. Shut down the computer.
3. Remove the Sonnet Tempo Pro which holds the Monterey drive and its backup.
4. Boot holding PRAM until I heard the second bong which then booted into the clean install of Mojave.
5. Shut down.
6. Install the Sonnet Tempo.
7. Boot, which showed the boot picker with Mojave (x2 because its backup also shows up for some reason, whereas the Monterey backup doesn't) Monterey, selecting the latter.
8. Restore the full Mojave backup to the main Mojave drive.

I had previously put OCLP also on the (Dosdude) Mojave drive which I suspect wasn't a good idea. Perhaps it doesn't make a difference to do this but in any event it worked.

br
Philip

remove monterey drive, do a pram reset and see what happens.