PC-3000 Forum

A customer brought in:

1X Seagate 2.5" 2TB
1X Seagate 2.5" 1TB SSHD

They were both in his macbook. (he removed the CDROM and put in the additional drive, then enabled Fusion)

He says he can't access his data on his mac and that he was using "Fusion" with these two drives. Is Fusion simply RAID with a fancy Apple name?
If so, what type of RAID could it be, JBOD?

it looks like it has "core storage" on it aswell.
My plan was to image both drives and rebuild the array.

No, fusion is more complex than just a RAID. It's a SPAN of sorts, but MacOS does move data around to keep the most commonly used files on the SSD instead of the HDD it also has a large write buffer on the SSD. I've tried writing various test patterns to fusion setups to see if there's a way to make sense of it and possibly re-assemble it at a bloc level and I've come to the conclusion that it can't be done by any simple method.

You'll need to do it with a Mac computer, it's the only way I've ever found that works. The good news is, if they didn't break the core setup, MacOS should recognize the drives (or even clones of them) on its own once you connect them both to the mac. Just be sure that if you're connecting clones that you set your max LBA to match the original drives.

And yes, Fusion is always using core storage and it may or may not be using FileVault encryption as well.

Let me correct myself... my plan is to image the whole drives onto 2 others the same size and just put it back in the same mac laptop....

That should work, or you can just connect them to any Mac you want. I've got a Mac Mini here with a couple USB docks plugged in. I just get good clones, set max LBA to match, then plug them in an wait for the OS to mount them. It's when you can't get a good clone or when a foolish computer guy nukes the SSD that it gets really interesting.

So core storage is universal and not user machine specific?
Is it neccessary to modify LBA? Pc3k can do it?

If you have both devices imaged you can rebuild these with R-Studio - potentially you can work with disk images as opposed to restoring to new disks and importing to a MAC OS system

osity wrote:Source of the post So core storage is universal and not user machine specific?

Yes, it's all part of the Core Storage LVM architecture. Another Mac will readily recognize it.

osity wrote:Source of the post Is it neccessary to modify LBA?

I believe it is, otherwise, it might get confused on the layout.

osity wrote:
Source of the post Pc3k can do it?

Yes, just check the max LBA of the original drive and SSD, then do "Set Max LBA" on your destination drive (with it connected on PC3K channel) and set it to match. It's just setting an HPA, you could even do it with a bit of Linux-foo if you'd like.