HDD (HFS+) combined with SSD (APFS)

diewal wrote:

Hi,

Recently I've replaced the optical drive in my late 2009 imac with a 500 GB SSD. I've reinstalled OS X high Sierra on that SSD and startup is very fast now! But I also have my 1 TB HDD drive in my Imac but I cannot see it when I choose the SSD as a startup disk. I can only access my HDD when I reboot and choose the HDD as startup disk (but then everything is very slow again). I do have a time machine backup and even a superduper backup of my HDD.

How can I let both drives (HDD & SSD) work together, or at least see the data on the HDD when I startup with the SSD? The purpose is to have the OS X and some apps running on the SSD while keeping the data itself on the HDD.

I was considering creating a fusion drive, but that is not recommended with the APFS filesystem format.

So the situation is as follows :

1 TB HDD with the HFS+ filesystem format (With OS X high sierra)

500 GB SDD with the APFS format. (also with OS X High Sierra)

Can I format both drives to APFS? Can I restore the TM or Superduper backup then? Will I be able to see all the stuff on my HDD when starting up with the SSD?

Thanks for the advice!

Kind regards,

Dieter

Any time that one does hardware changes on a Mac, you should

really do a PRAM reset (Reset NVRAM or PRAM on your Mac - Apple Support).

It basically reloads the hardware configuration.

If that brings the HDD back to being visible, I suggest not formatting

the HDD to APFS. HDD are not really suited for APFS.