Boot from DIY Fusion Drive

[Tanax]

Does anyone know if it's possible to boot from a Thunderbolt-connected DIY Fusion Drive(e.g. both the SSD and the HDD is external)?

 

[Tanax]

Anyone? I did search for it but I didn't find anyone where they had both drives externally, they only had 1 drive externally and the other one internally.

 

[Nuke61]

Anyone? I did search for it but I didn't find anyone where they had both drives externally, they only had 1 drive externally and the other one internally.

There's no reason to think it wouldn't work, especially since Thunderbolt connected drives look like internal drives - PCI bus connected.

 

[Tanax]

There's no reason to think it wouldn't work, especially since Thunderbolt connected drives look like internal drives - PCI bus connected.

I was just thinking that since the Fusion Drive basically is a software RAID and the software is actually on the fused drives.. when booting from it, will it recognize the 2 external drives as 1 Fusion Drive or will it recognize it as 2 external drives?

 

[Nuke61]

I was just thinking that since the Fusion Drive basically is a software RAID and the software is actually on the fused drives.. when booting from it, will it recognize the 2 external drives as 1 Fusion Drive or will it recognize it as 2 external drives?

I have no reason to think it would be seen as an external anything, because Thunderbolt is an extension of the internal bus, so drives are seen as internal. If I get another external drive it'll be the Buffalo MiniStation Thunderbolt, and in that case I'll try it and report results. Right now I'm just trying to get my Synology NAS set up.

 

[benwiggy]

I was just thinking that since the Fusion Drive basically is a software RAID and the software is actually on the fused drives..

If by "the software is on the fused drives" you mean that the OS sits on the FD and controls it at the same time, then yes.
However, tt's no different from booting up an internal Fusion drive. As said, the only difference is that it's outside the chassis rather than inside.

 

[Tanax]

Alright, cheers guys 🙂

@up- Yes, that's why I was worried. The software (meaning the OS) sits on the FD and controls it at the same time, when booting the OS I just assumed the "FD" wouldn't get recognised since the OS hadn't booted up yet.

Now that I think about it, I guess it really shouldn't be any different than booting from internal!

 

[Nuke61]

Now that I think about it, I guess it really shouldn't be any different than booting from internal!

I verified that it works as expected. I got another Buffalo MiniStation Thunderbolt drive, used Terminal with instructions I found in a search and created an external drive by fusing a 256GB 840 Pro with the Buffalo 1TB HDD, bith in Thunderbolt enclosures. I did a SuperDuper! clone and rebooted; worked fine.

As an FYI, while running from this DIY fused drive, I pulled one of the drive connectors and within a few seconds the Mac locked up. I rebooted normally and broke the fused drives back into their normal configuration.

 

[Tanax]

I verified that it works as expected. I got another Buffalo MiniStation Thunderbolt drive, used Terminal with instructions I found in a search and created an external drive by fusing a 256GB 840 Pro with the Buffalo 1TB HDD, bith in Thunderbolt enclosures. I did a SuperDuper! clone and rebooted; worked fine.

As an FYI, while running from this DIY fused drive, I pulled one of the drive connectors and within a few seconds the Mac locked up. I rebooted normally and broke the fused drives back into their normal configuration.

Awesome! Thank you 😀