I have a 2017 iMac. following bad advice from Carbon Copy Cloner, I managed to break my fusion/Hard drive connection.

rwnolan1001 wrote:

I was upgrading to an 2TB SSD drive. I used a standalone drive cloner. I cloned the drive and installed the SSD. I was unable to extend the 1TB into the 2TB space available.

Did you remove the HDD component of a Fusion Drive and stick it into an external hardware drive cloner?!? I can see two problems with that:

1. The HDD component of a Fusion Drive doesn't contain a complete volume ... just part of one.
2. The cloner copied everything exactly (down to partition sizes), whereas Carbon Copy Cloner or SuperDuper! would probably have been happy to back up a bootable 1 TB volume (that happened to be on a Fusion Drive) onto a 2 TB destination volume. (That is, assuming the Fusion Drive was still in one piece.)

Following CCC advice I put the Hard drive into the USB port and had the SSD inside the imac. I was going to clone the SSD from the 1TB hard drive in the hopes that it would allow me to extend the partition. no go - both drives had the same identifier.

Did they know that you had a Fusion Drive, before they gave you this advice?

SO unable to boot from the USB drive

No surprise there.

I have a backup copy of the SSD created from the spinning drive - that has not been on the computer ever.

Is this a bootable backup copy of the intact Fusion Drive, created using Carbon Copy Cloner? Or is it a second-generation clone of the HDD that contained only part of the contents of the Fusion Drive?

If it is a proper bootable backup of the entire Fusion Drive, you could use it as an external startup disk (and then immediately make a full backup of it to another drive, for safekeeping.)

Is there a way to remarry the fusion drive portion to the SSD/spinning drive image so I can boot again? - is there away to create a boot USB to bring the SSD/Spinning drive into the bootable world and screw the Fusion drive.? Or am I just screwed because I have no time machine backup.

You might need to enlist the aid of a service shop, or of a friend, who has a Mac of the same vintage as yours, to prepare a bootable external drive so that you can start up your Mac and carry out recovery tasks.

I don't know offhand whether you can repair the Fusion Drive or whether you'll just have to settle for getting the Mac to a point where you can install a new copy of the OS on your SSD. But you'll need to be able to boot your Mac before you can do either, and I'm guessing that the Recovery system might not be working on your system right now.

We used CCC exclusively for five years on my wife's Fusion Drive 2015 27" iMac Retina.

A single point on a graph dose not indicate a trend, but CCC was always easy to use and did exactly as advertised which was exactly what was needed..

We in fact still use CCC to make Time Machine type backups on out five Macs. Has never failed to work flawlessly.

For cloning, I now prefer SuperDuper!. I simply like the SD! interface better. CCC did a fine job of that too. Still does as far as I know.

You should have cloned the Fusion Drive as a whole to the external drive before splitting up or removing either drive from the iMac. If the Fusion Drive had already failed, then the only way to recovery from that, is to restore from your Time Machine or a clone backup on an external drive.

"I used CCC on my son's Macbook years ago. I believe we plugged the drive in as a USB and then CCC'd the internal to the USB. after that we swapped drives. The advice from CCC (in an email) said to pull the drive swap first then clone it... That obviously did not work. SO my next step to recover is ?"

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I don't understand your point. A clone is used in order to have an available working system in the event of a catastrophic internal system failure. Maybe just me, but I don't think of clones as a restoration sources, but as stand alone continued production-allowing entities. It's just too easy and convenient to use a backup app such as Time Machine, or CCC for that matter, to create a backup dataset.

Restoring a system/drive is generally done from a backup of some sort such as Time Machine and CCC are capable of creating.

Are you trying to restore your system from a cloned drive?

My dealings with CCC have been numerous and instructive. But since they're helping by remote means, you have to explain to them in excruciating detail exactly what you want to do. My guess is CCC didn't fully understand your need or the circumstances surrounding it.

"to pull the drive swap first" makes no sense to me.

" after that we swapped drives" Why were you swapping drives? What drives?

All I've ever done with CCC is attach the external drive to the Mac and have CCC use it. What's all the pulling and swapping got to do with anything?

The Fusion Drive was a good idea when it first came our, when SSDs were small and expensive. The idea was for each part of the Fusion Drive to counterbalance some of the worst aspects of the other, so that you got a workable compromise that for many people, would be better than just a small, expensive SSD, or a large, slow HDD.

A Fusion Drive is not meant to be disassembled by the average computer user any more than an automatic transmission is meant to be torn down by the average car or truck driver. That doesn’t make automatic transmissions or Fusiin Drives inherently bad engineering design; it just is what it is.

Option 1) Erase the new SSD and install macOS in Recovery Mode, then restore or migrate from a backup.

Option 2) Return the original drives to the iMac, refuse the drives and the restore from a backup. Then clone the Fusion Drive to the SSD externally and change out the drives.

Sadly if you did not have or create a good backup and set it aside before taking on this endeavor, then you are S.O.L. when it comes to migrating or restoring.

"Apple has backed away from it."

Yes, Apple did but they did so as SSD technology matured and prices plummeted. My wife's 2015 27" iMac had a Fusion Drive. Other than it being slower than she wanted, it was still faster than my 21.5" 2015 iMac's 5400 RPM internal HDD, she wanted a newer model after five years of very successful usage.

"is there a way to access the HDD (or cloned SSD) to recover the files". (Emphasis added)

It's a clone, an exact duplicate of the internal drive. There's no recovery to be done. All you do is boot from the drive and then copy the data off to an external drive. Or you can run Time Machine or CCC from the clone and create a backup dataset from it of it.

"SSD's do go bad and if you store part of your drive info on it you are screwed"

Yes they do, but so does every other device created by humans. That's why you make and verify backups. SSDs now days are no more prone to failure than HDDs. Apple is so convinced of that the latest Macs have the SSDs integrated into the logic board as a non removable component.

Is there a way to remarry the fusion drive portion to the SSD/spinning drive image so I can boot again?

Apple has this:

How to fix a split Fusion Drive