I have cloned the new 4TB Samsung 870EVO from the Fusion Drive on my late 2015 27inch iMac. When I switch the fusion for the ssd and try to boot up I just get the circle with the line through it. Both drives are formatted APFS and I have run Disc Utility First Aid which says everything is fine.
When I swap the old fusion back in the machine boots up fine.
What am I doing wrong?
iMac 27″, macOS 12.7
The other thing to check: When you removed the Fusion Drive, did you remove BOTH parts: the SSD and the HDD?
If you left the Fusion Drive intact (in software), but then removed just one of the hardware components, the one that was left would contain PART of a volume. Just a wild guess, but the Mac might not be too happy if it tried using that partial volume, and then encountered unexpected errors because the other half was missing.
Did you have Monterey installed on your Mac before you put in the third-party SSD?
In other threads, people have mentioned that the Monterey installer will check the firmware version on your Mac, and will run a firmware updater if necessary. The firmware updater may fail if it sees a non-Apple internal SSD … and if it fails, the Monterey installation will fail, as well.
Once you have installed Monterey once, successfully, anywhere, your firmware is updated, and you can then put in your external SSD and reinstall Monterey to your heart's content.
I guess that you cannot clone the disk and boot from a mounted image. Install a fresh macOS on the SSD instead and put back a Time Machine backup after that
I concur with WheelieNick. Instead of cloning, you need to install macOS on the 4T Samsung, then migrate from your Time Machine backup or the intact Fusion Drive.
Reinstall macOS Monterey over the top of the clone on the 4T SSD, then see if you are able startup from it.
If not, start over using Recovery Mode to erase and install macOS Monterey on the 4T Samsung, then migrate from your Time Machine backup or the intact Fusion Drive.
Startup from your Fusion Drive.
Go to > How to download and install macOS - Apple Support
Click on Monterey to open it in the App Store.
Download, open and install it on the external SSD.
Yes, Monterey was installed on the Fusion Drive (and still is) This drive still works fine when I swap it back into the iMac. I just don’t understand why I get the circle with line through it when I switch to ghe SSD which is, or should be a perfect carbon copy of the drive that works.
Yes, Monterey was installed on the Fusion Drive (and still is) This drive still works fine when I swap it back into the iMac. I just don’t understand why I get the circle with line through it when I switch to ghe SSD which is, or should be a perfect carbon copy of the drive that works.
Success and failure. I booted with the Fusion in recovery mode and followed the prompts and installed Monterey on the ssd ( was attached with usb)
rebooted using ssd as startup and all good. Fantastic thanks for advice to get here. But now with ssd installed I get nothing when I boot. Nothing at all on screen. Mac is starting, fan is turning. Must be a problem with display connections. Checked them and they seem physically ok. Any idea what’s going on now?
The instructional videos I watched on YT said no need to remove the small flash drive component of the Fusion Drive.
Thanks. So erase the SSD then install Monterey on it? Not sure how to do that install as Apple doesn’t make it available anymore as far as I know.
Thanks and excuse my ignorance but how exactly do I reinstall Monterey ‘over the top of the clone on the 4T SSD’?
Problem replacing iMac Fusion Drive with SSD
