Drobo 5C - Bootable backup

[Sigi]

Hello,
I have used for many years a 2Gen Drobo, firewire as my bootable backup created by Superduper. I was always able to boot from it if needed. This Drobo failed after many years of usage.

I have now a Drobo 5C, directly attached with USB and I can not boot from it anymore. I can select it in Preferences/Power+option but it ultimately boots from the HD. Bootable Backups are done by Superduper

I am on High Sierra, everything updated.

How can I fix this?

Thanks

 

[Fishrrman]

What computer do you have and what year was it made?

 

[Sigi]

What computer do you have and what year was it made?

It is an Imac 27inch, Late 2012, with a Fusion Drive.

 

[priitv8]

Do you see your Drobo in boot picker (holding down Alt key while booting)?

 

[Sigi]

If you mean press Power+alt key, yes, I can select the Drobo as a drive to boot from. But nevertheless ultimately the Mac boots from the HD.

The same in Preferences. I can select the Drobe as a start-up disc but the Mac starts nevertheless from the HD

 

[Fishrrman]

Have you tried the new Drobo with another Mac?
To see if it could boot that one?

 

[Sigi]

No, I do not have another one I could try that

 

[chabig]

This aapple support document has some troubleshooting tips:

Change your Mac startup disk

Change the startup disk of your Mac using Startup Disk settings.

support.apple.com

If you mean press Power+alt key, yes,

It’s just the option key. The power key starts the computer. The option key brings up the boot picker. See

Mac startup key combinations - Apple Support

Learn about the Mac features and tools that you can access by holding down one or more keys during startup.

support.apple.com