I was under the impression you couldn't install High Sierra on a Fusion Drive right now, but my iMac keeps prompting me to upgrade. Have things changed? Is it safe to do so?
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High Sierra on Fusion Drives
- Thread starter britabroad
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Oh, you can definitely install High Sierra on a Fusion Drive. What you cannot do is format a Fusion Drive with APFS, the next generation filesystem that is optimized for flash storage.
If you choose to upgrade your iMac to High Sierra now, your Fusion Drive would remain an HFS+ formatted volume. One of the Apple engineering VPs (Federighi?) mentioned earlier this year that APFS will be coming to Fusion Drives at a later date.
I am running High Sierra on three machines (2010, 2013, 2017) with no problems. Some people here have encountered various problems with High Sierra, so you might want to hold off for now. That's your call.
macOS 10.12 Sierra is a fine operating system and will still receive occasional security updates.
If you choose to upgrade your iMac to High Sierra now, your Fusion Drive would remain an HFS+ formatted volume. One of the Apple engineering VPs (Federighi?) mentioned earlier this year that APFS will be coming to Fusion Drives at a later date.
I am running High Sierra on three machines (2010, 2013, 2017) with no problems. Some people here have encountered various problems with High Sierra, so you might want to hold off for now. That's your call.
macOS 10.12 Sierra is a fine operating system and will still receive occasional security updates.
I haven't had an answer to this one yet, but my system is as follows:
Boot: PCIe SATA III SSD - contains all apps and a spare admin User account (so I can still log on if my FD doesn't work)
User data: Fusion Drive (FD) consists of a PCIe NVMe blade + HDD Spinner (in SATA II direct connect bay)
I guess my boot SSD will be converted to APFS if I upgrade to HS, but will it play nicely with my FD with my main User data? Will it try to convert the NVMe to APFS and therefore break my FD?
The main thing is my boot OS isn't actually on the FD - just my User data is on the FD. So can HS play nicely with User data on a HFS+ FD?
Boot: PCIe SATA III SSD - contains all apps and a spare admin User account (so I can still log on if my FD doesn't work)
User data: Fusion Drive (FD) consists of a PCIe NVMe blade + HDD Spinner (in SATA II direct connect bay)
I guess my boot SSD will be converted to APFS if I upgrade to HS, but will it play nicely with my FD with my main User data? Will it try to convert the NVMe to APFS and therefore break my FD?
The main thing is my boot OS isn't actually on the FD - just my User data is on the FD. So can HS play nicely with User data on a HFS+ FD?
Yes! I have been running Fusion on High Sierra for a month now. All worked well until yesterday, when the screen turned to Black & White.
High Sierra will install on fusion drives, but it will not convert the drive to APFS.
I'm wondering if Apple is ever going to support APFS on fusion -- I'm thinking "no".
But that's NOT IMPORTANT. HFS+ is a proven file system.
If you want High Sierra and you have fusion, install "what works".
That would be... HFS+.
I'm wondering if Apple is ever going to support APFS on fusion -- I'm thinking "no".
But that's NOT IMPORTANT. HFS+ is a proven file system.
If you want High Sierra and you have fusion, install "what works".
That would be... HFS+.
So are you saying that if I install HS on my PCIe SATA III SSD, that it will play nicely with my NVMe+Spinner HD Fusion Drive that has all my User data on it? I'm holding off from upgrading to HS until I know that HS won't ruin my FD.
macOS: Accelsior S PCIe SATA III card with a Samsung 850 EVO - for macOS and apps. Can you confirm it will convert this to APFS?
User data: Samsung 960 EVO NVMe in a fusion drive with a 2TB Hard disk drive (spinner). Can you confirm it will leave the NVMe alone and it will not try to convert it to APFS, which would break the FD.
macOS: Accelsior S PCIe SATA III card with a Samsung 850 EVO - for macOS and apps. Can you confirm it will convert this to APFS?
User data: Samsung 960 EVO NVMe in a fusion drive with a 2TB Hard disk drive (spinner). Can you confirm it will leave the NVMe alone and it will not try to convert it to APFS, which would break the FD.