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macOS 12 Monterey on Unsupported Macs Thread
- Thread starter khronokernel
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[I posted this on Sequoia thread, will leave it here too in case it helps anyone]
Just some tips on dual booting MacOS, with the last supported OS on one volume plus an OCLP MacOS on another volume. I'm dual booting my 2012 Macbook Pro and had some headaches of high cpu usage and slowness while switching OSes, after a long time trouble shooting this is what I found out:
Mac OS was never designed to dual boot between versions, it's designed to upgrade the OS only, and therefore when you start up the newer OS it immediately detects an older indexing Spotlight DB and starts to update it to the new version, hence the slowness on start, I was getting the new OS installed feeling every time, seeing a high mds_stores process cpu usage. And when I return to the older OS it detected a unsupported Spotlight DB, discards it and started over the indexing.
There's two solutions for this, you either disable Spotlight on every volume that are accessed from both OSes, by adding the volume on Spotlight Privacy list, inside Spotlight settings. This sets a flag on the volume itself, so both OSes will know not to index that volume. You will lose the ability to search for files using Spotlight for that volume.
The other option is prevent the auto-mount of the volume that you don't want Spotlight touching, by adding the Volume UUID using "sudo vifs", Google this for more precise instructions.
I use a combination of both, by preventing the OS to mount the other OS volume, thus keeping Spotlight, and I have other Volumes for personal files storage with Spotlight disabled, so I can access them on whichever OS is running.
Additionally, for the last supported MacOS to run "vanilla", with all security enabled, you have to uncheck NVRAM WriteFlash on OCLP, rebuild and install OpenCore, and perform the NVRAM reset once, by holding Option-Command-P-R keys when powering on. After that you should only boot to the supported OS by holding the Option key (leave OCLP for newer OS only). This will keep both OS NVRAM settings clompletely separated. You can check the security by running: csrutil status
Just some tips on dual booting MacOS, with the last supported OS on one volume plus an OCLP MacOS on another volume. I'm dual booting my 2012 Macbook Pro and had some headaches of high cpu usage and slowness while switching OSes, after a long time trouble shooting this is what I found out:
Mac OS was never designed to dual boot between versions, it's designed to upgrade the OS only, and therefore when you start up the newer OS it immediately detects an older indexing Spotlight DB and starts to update it to the new version, hence the slowness on start, I was getting the new OS installed feeling every time, seeing a high mds_stores process cpu usage. And when I return to the older OS it detected a unsupported Spotlight DB, discards it and started over the indexing.
There's two solutions for this, you either disable Spotlight on every volume that are accessed from both OSes, by adding the volume on Spotlight Privacy list, inside Spotlight settings. This sets a flag on the volume itself, so both OSes will know not to index that volume. You will lose the ability to search for files using Spotlight for that volume.
The other option is prevent the auto-mount of the volume that you don't want Spotlight touching, by adding the Volume UUID using "sudo vifs", Google this for more precise instructions.
I use a combination of both, by preventing the OS to mount the other OS volume, thus keeping Spotlight, and I have other Volumes for personal files storage with Spotlight disabled, so I can access them on whichever OS is running.
Additionally, for the last supported MacOS to run "vanilla", with all security enabled, you have to uncheck NVRAM WriteFlash on OCLP, rebuild and install OpenCore, and perform the NVRAM reset once, by holding Option-Command-P-R keys when powering on. After that you should only boot to the supported OS by holding the Option key (leave OCLP for newer OS only). This will keep both OS NVRAM settings clompletely separated. You can check the security by running: csrutil status
I am trying to install Monterey (12.7.4) via OCLP onto a 2011 iMac. I made an installer using OCLP 241 but it will not install. The internal hard drive is erased and formatted APFS. It was originally running High Sierra.
Whenever I boot the flash drive into the recovery (I assume) where I get the install option it fails after choosing the drive to install on.
Error: "An Error occurred while Preparing the installation. Try running this application again."
Also I have no wifi (no routers listed, nor connect via using name) when I boot using the OCLP EFI boot so this might be a reason the update wont proceed? I don't know. When I boot into the native recovery Wifi connects works fine, so obviously OCLP is causing this somehow.
So I am stuck right now as all I have is the OCLP created USB flash drive with a Monterey installer. On the 'native' iMac recovery boot it never contacts the recovery software server so fails every time to reinstall High Sierra.
Any suggestions regarding how to proceed from here?
Thnx
Whenever I boot the flash drive into the recovery (I assume) where I get the install option it fails after choosing the drive to install on.
Error: "An Error occurred while Preparing the installation. Try running this application again."
Also I have no wifi (no routers listed, nor connect via using name) when I boot using the OCLP EFI boot so this might be a reason the update wont proceed? I don't know. When I boot into the native recovery Wifi connects works fine, so obviously OCLP is causing this somehow.
So I am stuck right now as all I have is the OCLP created USB flash drive with a Monterey installer. On the 'native' iMac recovery boot it never contacts the recovery software server so fails every time to reinstall High Sierra.
Any suggestions regarding how to proceed from here?
Thnx
Your USB flash drive might be damaged or something went wrong when you created it.
Internet is not necessary to install, only the OCLP created flash drive. Sometimes retrying several times the installation continues, especially during the first reboot during the installation you might need to select OCLP EFI manually first, then choose the newly created volume (not the flash drive).
WiFi will only be available after installation when the post install patches are applied. If needed to recover to original MacOS try using an ethernet cable, is much more reliable during installations. To recover from the internet hold CMD + OPT + R after turning on the Mac.
Also try reseting the NVRAM (like BIOS on a PC), by holding CMD + OPT + P + R after turning on the Mac.
And since High Sierra is APFS compatible you don't have to erase it to install another MacOS version, just create another volume.
Erased and recreated the USB. Bit of an effort since I had to first install HSierra again to get OCLP running (I had wiped the drive prior to attempting the install) but fortunately that worked! Musta been a problem with the flash drive installation. Thanks.