Late 2012 iMac - Catalina / S.M.A.R.T.

[uptownnyc]

I'm running a 27" Late 2012 iMac with 32gb of RAM and initially configured with the 3tb Fusion Drive. It was subject to the recall program, so the fusion drive was swapped out by Apple once. Eventually, that drive also failed -- so I replaced it myself with one of the OWC DIY drive-replacement kits. They provided me with a 4tb drive which eventually failed, indicating S.M.A.R.T errors were present, preventing me from installing a MacOS update. That drive was replaced under warranty, leaving me with a 6tb internal drive that I installed 3 months ago, and which I've split using the normal Fusion Drive partitioning steps. I used the stick-on sensor with the upgrade kit and followed all the instructions and everything is working without an issue.

Last night I decided to give the Catalina update a go since Apple keeps reminding me that it's available. Upon attempting to install, the installation routine is again telling me that I have S.M.A.R.T. errors on the drive. Possible? I suppose. Probable? I don't see how it could be. The drive is new. It's performing without issue. And when I run the health check, I encounter no issues whatsoever.

I realize I've gotten more than my use out of the thing. It's from 2012 and we're in 2020 -- but it's still operating very well, aesthetically looks identical to the current models (apart from the lack of a retina display), and it's not clear to me why I continue to get S.M.A.R.T errors.

I'm guess I'm fine sticking with Mojave, but any ideas what might be causing this issue, or how to resolve it?

 

[Khaleal]

Just install a 2.5” SSD instead of the HDD, and connect the HDD externally

 

[uptownnyc]

Just install a 2.5” SSD instead of the HDD, and connect the HDD externally

What are my options regarding sizing this drive with regard to TimeMachine? My current internal drive is 6tb, but I'm only using 1.88TB. Presumably a 2TB SSD would suffice for a full restore, but is there a way to go with a smaller SSD yet still restore from a TimeMachine backup so that I don't need to start from scratch with MacOS setup and configuration?

 

[mbosse]

I'm running a 27" Late 2012 iMac with 32gb of RAM and initially configured with the 3tb Fusion Drive. It was subject to the recall program, so the fusion drive was swapped out by Apple once. Eventually, that drive also failed -- so I replaced it myself with one of the OWC DIY drive-replacement kits. They provided me with a 4tb drive which eventually failed, indicating S.M.A.R.T errors were present, preventing me from installing a MacOS update. That drive was replaced under warranty, leaving me with a 6tb internal drive that I installed 3 months ago, and which I've split using the normal Fusion Drive partitioning steps. I used the stick-on sensor with the upgrade kit and followed all the instructions and everything is working without an issue.

Last night I decided to give the Catalina update a go since Apple keeps reminding me that it's available. Upon attempting to install, the installation routine is again telling me that I have S.M.A.R.T. errors on the drive. Possible? I suppose. Probable? I don't see how it could be. The drive is new. It's performing without issue. And when I run the health check, I encounter no issues whatsoever.

I realize I've gotten more than my use out of the thing. It's from 2012 and we're in 2020 -- but it's still operating very well, aesthetically looks identical to the current models (apart from the lack of a retina display), and it's not clear to me why I continue to get S.M.A.R.T errors.

I'm guess I'm fine sticking with Mojave, but any ideas what might be causing this issue, or how to resolve it?

Could you install a system on the SSD part, then install DriveDx (has a free 15 days trial period) and post a screenshot of the SMART data from the HDD?

What are my options regarding sizing this drive with regard to TimeMachine? My current internal drive is 6tb, but I'm only using 1.88TB. Presumably a 2TB SSD would suffice for a full restore, but is there a way to go with a smaller SSD yet still restore from a TimeMachine backup so that I don't need to start from scratch with MacOS setup and configuration?

I would guess no. Also, if you are already using almost the full 2 TB of the SSD, I would never use a smaller on, particularly also because your next best option would be 1 TB (except for a few rare Intel 1.2 or 1.6 TB server SSDs). I would even go as far and use a 4 TB SSD right away. Samsung 860 QVO might be a feasible option (and you won't need to use the OWC temperature sensor).

Best,
Magnus

 

[uptownnyc]

So it seems the Apple SSD is failing, while the 6tb replacement drive is fine.

 

[mbosse]

So it seems the Apple SSD is failing, while the 6tb replacement drive is fine.

View attachment 921764

View attachment 921765

Exactly. The Apple SSD is dead. First time I see such an SSD worn out.
Could you post a screenshot of the health indicators as well? Curious to see how many terabytes you have written on it.

thanks,
Magnus

 

[uptownnyc]

Exactly. The Apple SSD is dead. First time I see such an SSD worn out.
Could you post a screenshot of the health indicators as well? Curious to see how many terabytes you have written on it.

thanks,
Magnus

 

[Khaleal]

Well, then just buy a second hand apple SSD (blade) off eBay and rebuild the fusion drive with the new SSD, then you'll be able to restore your time machine without any issues.

 

[mbosse]

Well, then just buy a second hand apple SSD (blade) off eBay and rebuild the fusion drive with the new SSD, then you'll be able to restore your time machine without any issues.

This!

 

[uptownnyc]

Assuming I don't want to open my iMac for a 3rd or 4th time -- I presume a good USB 3.0 external SSD could be used as my boot drive, while still utilizing my internal 6tb drive for capacity. Similar to what Khaleal had suggested. Is that a viable approach?

 

[SaSaSushi]

Assuming I don't want to open my iMac for a 3rd or 4th time -- I presume a good USB 3.0 external SSD could be used as my boot drive, while still utilizing my internal 6tb drive for capacity. Similar to what Khaleal had suggested. Is that a viable approach?

Yes, you could boot from a USB 3 SSD. This would be the cheapest and easiest solution.

Alternatively, you could also get a Thunderbolt enclosure which would allow TRIM commands that I contend make a difference in performance for a boot drive.

Also, you can also upgrade SSD firmware in a TB enclosure, but not via USB.

I was using this Delock enclosure to boot my Late 2013 iMac for years. I'm still using it with an Apple TB1 to TB2 adapter on my Late 2017 iMac for a BootCamp Windows installation.

I wouldn't recommend this as an option for booting a TB3-equipped iMac but it's a good solution for the Late 2012.

 

[uptownnyc]

Yes, you could boot from a USB 3 SSD. This would be the cheapest and easiest solution.

Alternatively, you could also get a Thunderbolt enclosure which would allow TRIM commands that I contend make a difference in performance for a boot drive.

Also, you can also upgrade SSD firmware in a TB enclosure, but not via USB.

I was using this Delock enclosure to boot my Late 2013 iMac for years. I'm still using it with an Apple TB1 to TB2 adapter on my Late 2017 iMac for a BootCamp Windows installation.

I wouldn't recommend this as an option for booting a TB3-equipped iMac but it's a good solution for the Late 2012.

If I'm using an external SSD would I still be able to "fuse" it with the internal drive, or going forward I'd need to just treat them separately? So I'd have my boot-drive and my "stuff" drive.

I guess I'm just trying to figure out how I transition from my current setup (busted blade SSD that I'm going to stop using with 2tb of 6tb worth of data) to an external 500gb SSD and an internal 6tb HDD, and see if there's an easy way to restore my TimeMachine backup to get back to a functional state with minimal disruption.

 

[SaSaSushi]

If I'm using an external SSD would I still be able to "fuse" it with the internal drive, or going forward I'd need to just treat them separately? So I'd have my boot-drive and my "stuff" drive.

While you could fuse them there isn't any particular benefit to doing so and I would recommend just using the internal HDD as a storage drive.

I guess I'm just trying to figure out how I transition from my current setup (busted blade SSD that I'm going to stop using with 2tb of 6tb worth of data) to an external 500gb SSD and an internal 6tb HDD, and see if there's an easy way to restore my TimeMachine backup to get back to a functional state with minimal disruption.

I would recommend you restore from Time Machine to the new external SSD and when you get to step 6 to select information to transfer, unselect larger media/files as necessary.
Once you're back up and running you can always go into Time Machine and manually restore everything else to the internal HDD.

 

[uptownnyc]

I would recommend you restore from Time Machine to the new external SSD and when you get to step 6 to select information to transfer, unselect larger media/files as necessary.
Once you're back up and running you can always go into Time Machine and manually restore everything else to the internal HDD.

Great. I'll give this a try. Thanks all for the help understanding this issue.

 

[uptownnyc]

Finally received my new external SSD.

One more question before I go through this process. Since my current iMac has its internal drives fused (SSD + HDD), I'm assuming I'll want to un-fuse those before reinstalling MacOS to the new external SSD so that I have the two internal volumes separated for restoring larger files to the HDD, and decommission my use of the internal blade SSD.

Is this the basic sequence:

1. Ensure current system is backed up to TimeMachine
2. Reboot to Terminal
3. Un-fuse internal SSD and HDD drives
4. Reinstall MacOS to external SSD
5. Restore large files to internal HDD