Hard Drive Formatting & Enclosure Compatibility Issues on Mac

[Dochartaigh]

I can't find a drive format that works in all my Mac computers. I have a 2009 Mac Pro, 2017 Macbook 12-inch, 2023 Mac Mini M2 Pro.

If I format an internal drive in my 2009 Mac Pro server (I tried external drives on this too - but the 3x different USB 3.0 add-on cards I've tried are flaky over super long backups, and external drives running on the stock USB 2.0 is WAY too slow, so I usually mount the drive internally in a caddy), 5 out of 6 of my external enclosures will NOT read it. Prompt me with "the disk you attached was not readable by this computer" and lists 3x options: Eject, Ignore, or Initialize (i.e. format).

Even if I ignore the 2009 Mac Pro entirely (as I know that's super old and may be formatting in a way modern computers don't like), and switch to doing backups ONLY via my 2x most-used external enclosures (a Plugables and a Sabrent), on my way newer 2023 Mac Mini M2 Pro (which is networked to the Mac Pro where all the data is), this happens:

I format the drive in my Sabrent EC-DFLT enclosure (chipset: JMicron, Vendor ID: 0x152d, Product ID: 0x1561) via the default Disk Utility Mac OS Extended Journaled (tried MBR and GUID), and it works.
Move that SAME drive into the Plugable USBC-SATA-V (chipset: ASMedia ASM1153E, Vendor ID: 0x174c, Product ID: 0x1153), and it says "not readable".

When I do the opposite - format on Plugable, then put into Sabrent, and the same exact thing happens: "not readable".

This has happened constantly over the last 10x years. Doesn't matter if the drive is an enterprise drive from multiple manufacturers, or consumer drives by WD/Seagate I shuck from those cheap enclosures. Doesn't seem to matter which external enclosure either, as I've tried 6+ of them over the years, and the SAME EXACT thing happens constantly.


How can I get these drives to work in ANY enclosure, reliably? I simply can NOT be tied to one exact enclosure with one exact chipset inside it - what happens if that enclosure breaks? And they've changed the chipset in it on the new version (amazon reviews mention this ALL the time, same model bought later uses a different chipset)? That drive would then be unreadable, and my data lost. ...I'm simply not finding a way to make this happen and I've formatted these drives literally 3 dozen times all different ways... Also don't want to format ExFat for a whole plethora of past issues with that (just in case somebody mentions that).


(below this is more information if you really want it - mostly stuff I don't understand myself)

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If you want more information (which tbh is still WAY over my head) I dug into this really deep today, spent 5 hours reading forum posts and querying ChatGPT (always reading the source it got that info from, as ChatGPT is VERY flaky a lot of the time), trying all sorts of things - even formatting on a Windows computer in various ways which a Mac can't format them (something about 4K/4096 bytes vs. 512e vs. 4Kn formatting types, about 512 masquerading as actually 4K physical?), all to no avail... If the below makes more sense to you experts out there, I had ChatGPT summarize all the things we've tried and the issues seem to be:

8TB formatted in Plugable (4096 sector size) → Not recognized in Sabrent (512 sector expected).
8TB formatted in Sabrent (512 sector size) → Not recognized in Plugable.
Internal drives from 2009 Mac Pro don’t work in 5 out of 6 external enclosures, except the brand-new Plugable one

Likely due to non-standard MBR formatting that bypasses 2TB limit on the Mac Pro.
macOS Disk Utility formats in a way that’s NOT universally compatible

Disk Utility [on my 2023 Mac mini M2 Pro] formatted 8TB in MBR instead of GPT.
Mac Pro Disk Utility may have forced non-standard MBR.
Windows 10 Formatting Attempt (DiskPart)

Tried formatting in Windows with 4096-byte sectors, but still showed as 512e.
Windows formatted as NTFS 512e, but Mac wouldn’t read it correctly.
Had to reformat on Mac again, but still caused enclosure compatibility issues.

Current Goal [and I don't know if these are my goals or not... just want it to work]
I want a single universal formatting method so that my drives:
• Work internally in Mac Pro (2009) [I can totally give up on this one and just use external enclosures - I'm tired of manually inserting into caddies anyway...]
• Work in Plugable (USB-C)
• Work in Sabrent (USB-A)
• Are formatted with modern GPT (not old MBR tricks)
• Use Mac OS Extended (Journaled) HFS+ for maximum macOS compatibility
• Use 512e (not native 4K) for better enclosure compatibility

Questions for MacForums
How can I format the drives so they work in all my enclosures?
Is there a way to force 512e or a universal format?
Why does macOS sometimes format drives in MBR instead of GPT?
Even when manually choosing GUID, it sometimes forces MBR.

 

[HobeSoundDarryl]

Have you tried all of the combinations of formatting options that seem like they should work without forcing anything into the format (like the 512e option)?

Mac HFS+ formatting should work with the 3 Macs. It might help to define what macOS versions you are running instead of keying this on the hardware.

My first guess is that each enclosure wants boot data they way it wants it, so hopping drive from enclosure to enclosure may not be possible with any format. Consider allocating a drive to a single enclosure and another drive to another enclosure etc. Then share by moving enclosure from Mac to Mac instead of drive inside an enclosure to another enclosure.

If this is about easily sharing files between the 3, add a NAS enclosure and connect the three Macs to it over the network to share files. Or use cloud options if you trust cloud.

 

[Dochartaigh]

Have you tried all of the combinations of formatting options that seem like they should work without forcing anything into the format (like the 512e option)?

Mac HFS+ formatting should work with the 3 Macs. It might help to define what macOS versions you are running instead of keying this on the hardware.

My first guess is that each enclosure wants boot data they way it wants it, so hopping drive from enclosure to enclosure may not be possible with any format. Consider allocating a drive to a single enclosure and another drive to another enclosure etc. Then share by moving enclosure from Mac to Mac instead of drive inside an enclosure to another enclosure.

If this is about easily sharing files between the 3, add a NAS enclosure and connect the three Macs to it over the network to share files. Or use cloud options if you trust cloud.

I'm glad to fill-in the missing information - but to be honest with you this issue has been around for 10+ years for me, so literally every OS from El Capitan to Sequoia (or whatever the newest each of my older Mac's can run).

2009 Mac Pro has Mojave in it
2017 Macbook 12-inch has Ventura 13.7.2
2023 Mac mini M2 Pro has Sequoia 15.3 (maybe 15.2 - forget if I did the update this week)

And my only point is to get a foolproof offsite backup (i.e. networking/NAS won't help). You suggested I use a single enclosure with only one exact hard drive. What if that enclosure breaks? You then LOSE all your data - since there's NO guarantee you can buy that same exact model with that same chipset again, since all of these seem to switch chipsets between production runs pretty frequently. This would be in no way foolproof.

I can format ANY drive in NTFS, and literally every single one of my 6+ enclosures will read it (ok, I've probably only tested like 3ish enclosures on the same HDD before... but still, that's WAY better lol) ...it would be unfathomable if Mac can't do the same...

Anyway you said to try HFS+ formatting. Below is a summary of what I just did via following ChatGPT, and why it didn't work:

• Tested two enclosures:
  • Sabrent (JMicron chipset) → Forces 4K sector size.
  • Plugable (ASMedia chipset) → Defaults to 512e sector size.
• Formatted the drive as HFS+ (Mac OS Extended, Journaled) multiple times and tested switching enclosures:
  • Formatting as HFS+ in Plugable (512e) → Works in Plugable but not in Sabrent.
  • Formatting as HFS+ in Sabrent (4K) → Works in Sabrent but not in Plugable.
  • Even forcing HFS+ on a 4K-formatted drive in Plugable, Sabrent still didn’t read the drive.
  • Once a drive is formatted in either enclosure, the other enclosure cannot read it.
• HFS+ itself is not the problem. The issue is that the enclosures lock the drive into different sector sizes (512e vs. 4K). This makes them incompatible regardless of the file system.
• Potential cause:
  • The enclosures do not properly handle switching between sector sizes.
  • MacOS formats the drive based on what the enclosure reports, locking it into that mode.
• Conclusion:
  • If I format the drive in Sabrent, I can only use it in Sabrent.
  • If I format the drive in Plugable, I can only use it in Plugable.
  • There is no simple way to make the same drive work in both enclosures.

_______________

Beyond that ChatGPT summary of everything I tried, I know this ALSO holds true for all the other enclosures I've tested: Inateck, Orico, Lacie, Ugreen, even multiple ones I shucked the HDD's out of and kept the little SATA PCB board and the power supply for impromptu use... So again, I can't believe that a HDD has to be tethered to one single enclosure with one exact chipset in it - that would be insane, right? Like why even sell the enclosures which are open on the top for quick HDD swaps - there's literally 5,000 models of those... all of which say compatible with Mac... but they really don't work on Mac? I have to be missing something here...

 

[HobeSoundDarryl]

No, you could use 50 enclosures for 50 backups. I suspect the issue is you are trying to format a drive but then share it in multiple enclosures. So just leave a drive in one enclosure. And leave another drive in another enclosure. Etc. Then backup to however many enclosure + drive combos that you have. More simply: quit trying to move drives around to different enclosures. Install them and leave them in whatever enclosure in which you install them. Then just use each combo of enclosure + drive as a UNIT.

In short: give up on trying to make one drive be able to hop enclosure to enclosure. Instead, use a couple of drives and your couple of enclosures and install drives in your enclosures and just leave them there. Then backup your Macs to however many "UNITS" you have.

And one NAS enclosure loaded with a big drive could be a "whole home" backup for all 3 Macs (they all backup to that one over ethernet and/or wifi). And then allocate an enclosure + drive UNIT (DAS) to each Mac to be an additional backup for each Mac. If you have 3 Macs, use 3 "UNITS". If you have 5 Macs, use 5 "UNITS".

Store these 3 DAS units offsite and let your local NAS unit be your at-home backup. Fetch them regularly to freshen up the backups on them and then get them back offsite. Or if you have 6 DAS enclosures, skip the NAS and use 3 of them as your at-home backups and regularly rotate them with 3 offsite backups (so the offsite backups are always pretty fresh).

Lastly, if you don't have many enclosures beyond the 2 you reference, consider using bare drives and a bare drive dock. You can buy plastic cases for bare drives and those can be the drives you store offsite. This option would also fully address you concern about some enclosure breaking, as you would be using bare drives. You could replace the dock with any other dock and continue using the bare drives.

The key- which you seem to know- is to get at least 3 fairly fresh backups of your 3 Macs stored offsite. In simple thinking, this could be accomplished with 3 drives onsite and 3 more offsite. Or you could get as little as maybe 2 BIG HDD drives (20-24TB) split into 3 sizes suitable for each Mac to be backed up and then back each up to a single drive onsite. Rotate that regularly with the offsite one and then backup the 3 to the 3 segments on that drive. This would be only a 2-drive solution that could work for you. I do exactly this on a monthly schedule... PLUS also have a Synology NAS for whole home backups too.

Else, I don't think you'll find a format that is going to let a drive easily hop enclosure to enclosure (brand) and be usable... except with one of them HDD docks, which isn't really trying to "own" any HDD at all.

 

[Dochartaigh]

No, you could use 50 enclosures for 50 backups. I suspect the issue is you are trying to format a drive but then share it in multiple enclosures. So just leave a drive in one enclosure. And leave another drive in another enclosure. Etc. Then backup to however many enclosure + drive inside combos that you have. More simply: stop trying to move drives around to different enclosures. Install them and leave them in whatever enclosure in which you install them. Then just use that combo of enclosure + drive as a UNIT.

In short: give up on trying to make one drive be able to hop enclosure to enclosure. Instead, use a couple of drives and your couple of enclosures and install drives in your enclosures and just leave them there. Then backup your Macs to however many enclosures you have.

And one NAS enclosure loaded with a big drive could be a "whole home" backup for all 3 Macs (they all backup to that one over ethernet and/or wifi). And then allocate an enclosure + drive UNIT (DAS) to each Mac to be an additional backup for each Mac. If you have 3 Macs, use 3 "UNITS". If you have 5 Macs, use 5 "UNITS".

You're not addressing the issue of "foolproof" though. A backup which isn't reliable in all situations is NOT foolproof, nor 100% reliable.

Explain to me what happens when an enclosure breaks and you can't get that same exact enclosure again (dude, one little jar to where a cable goes into the PCB can break these SUPER easily...). ALL your data is lost. Why do you think I've mentioned 6x different enclosures I've owned? Because they CAN and DO break over the years.

Explain to me if your house burns down (like mine sadly did 20+ years ago) - a hard drive in a NAS isn't going to help you when it's a charred mess in your basement (trust me, I know for a FACT that HDD's do not like fire...).

And yes, I have cloud backup as well - but that doesn't help if I have a deadline and I need a massive Premier fileset downloaded, and it's so big their site won't let me download it, and I have to mail-order a HDD from them which takes time. Yeah, I totally just made that up lol, but there's a thousand other scenarios where a hard backup can save the day.

...I'm not asking for something crazy here - just how to format a Mac HDD which works in multiple enclosures, like Windows/NTFS seems to be able to do.

 

[HobeSoundDarryl]

You're not addressing the issue of "foolproof" though. A backup which isn't reliable in all situations is NOT foolproof, nor 100% reliable.

You say you've been trying for 10 years. There is very likely no "foolproof" in the direction you are trying to go.

Explain to me what happens when an enclosure breaks and you can't get that same exact enclosure again (dude, one little jar to where a cable goes into the PCB can break these SUPER easily...). ALL your data is lost.

You use a 2-drive solution if that works or perhaps a little more than 2 drives if up to 24TB total space split 3 ways is not enough for some of your Macs. If one drive fails, you replace that one drive, freshly backup to it and carry on.

You should never depend on only 1 backup drive or enclosure + drive. You need 2 full backups: one onsite and one fairly fresh offsite. And that is your near "foolproof" solution as you would then have:

• Original files on your 3 Macs
• A very fresh backup on the local backup drive (or drives) currently attached to them
• A pretty fresh backup on the local drive (or drives) offsite to soon be swapped with the one(s) at home.
• Maintain the regular rotation of onsite drive(s) and offsite drive(s) so the offsite is always a pretty fresh backup.

If you want to up that close to completely "foolproof" mix in at least one more backup drive(s) stored somewhere else offsite and regularly rotate this backup store too. Then a scenario that takes out all home backups and one offsite location still has a second offsite location to save the day(ta).

Why do you think I've mentioned 6x different enclosures I've owned? Because they CAN and DO break over the years.

Yes, drives and enclosures will fail. So don't depend on only 1. Get at least 2 backups for each Mac with one of those offsite and you are pretty secure. Add more backups if you want even more security.

Explain to me if your house burns down (like mine sadly did 20+ years ago) - a hard drive in a NAS isn't going to help you when it's a charred mess in your basement (trust me, I know for a FACT that HDD's do not like fire...).

Correct. The Mac(s) at home, the NAS and any DAS backups would all be lost in fire-flood-theft scenarios. That's why you have a recent, fresh backup stored offsite too. It protects against those very scenarios. If my house burns down and all data is lost there, I recover from the fairly recent backups I've stored offsite. I store mine in a bank safe deposit box and switch them when I'm going to be at the bank anyway.

And yes, I have cloud backup as well - but that doesn't help if I have a deadline and I need a massive Premier fileset downloaded, and it's so big their site won't let me download it, and I have to mail-order a HDD from them which takes time. Yeah, I totally just made that up lol, but there's a thousand other scenarios where a hard backup can save the day.

In any "what ifs" like this, I might just add another backup store at home... on perhaps old drives laying around doing nothing that still work... and regularly refresh those too (maybe monthly or so).

And if my latest data is so precious that I can't afford to lose even the last week or two freshest files, I much more regularly rotate my onsite-offsite backups or perhaps have a third that I'm tossing into my car every time I leave the home so there is a freshest backup not at home in case there is a fire-flood-theft while I'm out.

...I'm not asking for something crazy here - just how to format a Mac HDD which works in multiple enclosures, like Windows/NTFS seems to be able to do.

You may be. What you're asking for may be impossible based on how Macs format drives in various enclosures and/or how various enclosures manage their formatting for boot blocks. You seem to have thoroughly tried & tried & tried again to make this go and it is not. So "think different" and give up on the idea of shifting drives enclosure to enclosure and instead just have enough backup "units" to have your Macs freshly backed up at home AND recently backed up offsite.

 

[_timo_redux_]

Don’t use USB enclosures; use Thunderbolt enclosures

 

[Dochartaigh]

You may be. What you're asking for may be impossible based on how Macs format drives in various enclosures and/or how various enclosures manage their formatting for boot blocks. You seem to have thoroughly tried & tried & tried again to make this go and it is not. So "think different" and give up on the idea of shifting drives enclosure to enclosure and instead just have enough backup "units" to have your Macs freshly backed up at home and recently backed up offsite.

I agree with you... but still can't believe this is the case, because this is, well... just so friggin idiotic if this is how Mac has been making their HDD formatting work for at least the last 10 years I've been having this issue. Easier to use my butt lol.

I'm also posting because I honestly have very little knowledge of all this formatting stuff, and hoping that the experts here might have a solution which I haven't tried... because all I've tried is random solutions posted on like Reddit, and what ChatGPT (which is wrong SO friggin often...) has told me to try.

 

[Dochartaigh]

Don’t use USB enclosures; use Thunderbolt enclosures

Have a link to any true Thunderbolt ones which take single 3.5" drives up to 16TB+ in size? And would ANY OTHER Thunderbolt enclosure also work on a drive which was formatted in another Thunderbolt enclosure? Like this is a proven thing they specifically do, which non-thunderbolt enclosures do not do?

The Plugable one I've been talking about says it's "Thunderbolt 3"... but I honestly don't know if they just mean like USB 3.1 gen 2 over a USB-C connection, or if there's something else it needs to be qualified as such.

 

[HobeSoundDarryl]

I agree with you... but still can't believe this is the case, because this is, well... just so friggin idiotic if this is how Mac has been making their HDD formatting work for at least the last 10 years I've been having this issue. Easier to use my butt lol.

I'm also posting because I honestly have very little knowledge of all this formatting stuff, and hoping that the experts here might have a solution which I haven't tried... because all I've tried is random solutions posted on like Reddit, and what ChatGPT (which is wrong SO friggin often...) has told me to try.

I'm guessing you've tried all formatting options over 10 years of attempts. I doubt there is a magic one that will let the drive jump to different brands of enclosures and "just work" even if NTFS formatted drives have been able to do that.

I've been at this for a few decades and haven't come across many wanting to do what you are trying to do here. Usually, people insert a new drive in an enclosure and it will live there until it conks. It's usually at least a bit of trouble to move drives from one enclosure to another, so it's just easier to install it once and leave it there.

You might do the same with your (at least) 2 enclosures. If your drives are BIG enough to hold backups from all 3 Macs, let one be your at-home DAS and the other be your offsite DAS. If the drives are too small for that, you may need a few more drives and then you have perhaps 2 or maybe 3 drives at home and 2 or 3 drives offsite.

What I've done is purchased 2 big storage drives (24TB now available), and they rotate onsite-offsite regularly (monthly). I've also got a Synology NAS for another backup. It uses a RAID-like system for a built-in backup against 1 drive in the NAS failing. And I regularly sync my desktop Mac to my laptop so that my freshest files can be out with m in the laptop when I'm away from the drives at home. Fire-flood-theft takes out everything at home and I recover with the fairly fresh backup stored offsite and/or the freshest files on that laptop probably out with me. Maybe adopting some of that for your situation will work for you?

 

[Dochartaigh]

I've been at this for a few decades and haven't come across many wanting to do what you are trying to do here. Usually, people insert a new drive in an enclosure and it will live there until it conks. It's usually at least a bit of trouble to move drives from one enclosure to another, so it's just easier to install it once and leave it there.

See, me and pretty much all of my buddies which are into retro computers and modding video game systems and such are very fond of the open type HDD enclosures like I use as we're always switching out drives from devices with no ethernet/internet/network access (and/or so old it's so slow as to be nearly useless) with some pretty funky and proprietary formatting (like they only show up in special programs on the host computer - never in Finder or Explorer).

Like the Plugable one I've been talking about, you drop a bare HDD in from the top - the HDD is open to the air - not enclosed. Makes it easy to swap drives in and out without any tools and small screws (also takes both 2.5" and 3.5" so great for Laptop drives and the smaller SSD's as well). These are commonly the types I see on the desks of our IT department as well (which are all Windows/PC based of course).

My other enclosure, the Sabrent, is similar - little hinged door on top, open it up (no screws needed to be taken out) and slide a new drive in. Have a whole bunch of similar ones for older IDE drives too...

So these are the types I've been using for the last 20ish years. I use them for a lot of other things, but this time around I'm trying to shore-up my 'just in case' backup solution for my Mac ecosystem - and failing at it with how I want to do it... so yeah, may have to change it up if I can't figure this out.

 

[artifex]

Have you ruled out gpt vs mbr partitioning issues (everything should be able to read gpt)? Though 32-bit os versions probably can't read drives over 2 tb partitioned that way. And for the shucked drives that don't work without their shells, have you tried the kapton tape fix for possible 3.3v pin issues?

 

[Dochartaigh]

Have you ruled out gpt vs mbr partitioning issues (everything should be able to read gpt)? Though 32-bit os versions probably can't read drives over 2 tb partitioned that way. And for the shucked drives that don't work without their shells, have you tried the kapton tape fix for possible 3.3v pin issues?

I formatted the drive as GPT on the Plugable enclosure - then moved it to the Sabrent and it would not read it, and terminal said the Sabrent was reporting it as MBR weirdly enough... And just in case I made a mistake, I tried it again with the same exact result... Kinda the same funkiness with the 4k vs 512 between these two enclosures.

And those shucked drives still work perfect in any enclosure I've used - well 'perfect' meaning that the drive might say it can't read it until I reformat it, but once reformatted work PERFECT in that same enclosure... until perhaps I move it into another enclosure and the same exact kinda stuff happens which I've been talking about, and it won't be read in the other one.

For the tape fix, the only time I need to do that is when I'm putting newer drives into my 2009 Mac Pro (needed new sleds/caddies as well since they moved the screw holes on those as well!) - and not all of them need that. Like my enterprise grade 16TB didn't need that, but an even older 10TB one did... but that's kinda separate from this HDD enclosure issue, since those enclosures are newer they've never needed tape on any drive (although I have tried it with, just in the rare case that was the issue).

 

[Siliconguy]

Wow. I've never had anywhere near that much trouble. I just format hard disks as HFS+ journaled with the GUID (not APM and never MBR) and have no trouble. I have switched drives between enclosures, but those enclosures are all from the same company (OWC). I also have a drive formatted as ExFat for passing around since everything Intel-based can read that, including the Linux machines.

There was one problem child. Simply formatting it from Disk Utility wasn't enough, for some reason I had to partition it as a single partition, then goto the Options button and force that to GUID. Then the drive would work on the other machines.

I have a 2006, 2009, 2012, and 2014 Minis, and a 2010 Pro. They don't have much trouble sharing drives around. The tricky ones are the 2002 Quicksilver and the 2004 G5. They need APM formatting on HFS+ and can not read ExFat. The USB 2 cards can't supply enough power to spin up a 2.5" disk which is odd, so they need firewire 400 cases and those are getting scarce.

By the way, the 64 bit Intel Macs spend most of their time in Linux now. Mint 22.1 Cinnamon on the 2014 and 2010 Pro, and Mint 22.1 MATE on the 2009 and 2012.

 

[Dochartaigh]

those enclosures are all from the same company (OWC).

I think this is why - those most likely all use the same exact chipset in them. Some of these ones I use (like Amazon best sellers usually, so nothing super obscure, and by brands I know and own other things by them which I like), I can't even tell which chipset they use in the description - like have to go into the comments where different reviewers from different purchase years list a different chipset than somebody who purchased it a year or two before or after them... so very confusing.

I WAS just looking at the OWC Mercury Elite Pro I think it was though - can get enclosure-only for ~$70... but I would need a whole bunch of them... (when I've already bought have many other enclosures...)

 

[bzgnyc2]

I think you have a lot of variables running around here at the same time and that is confusing things. It appears you have drive format/sector size versus enclosures/chipsets versus versus filesystems/OS. I believe if the different enclosures present the underlying data to the OS the same way, they will be similarly readable.

Otherwise, generally moving drives among systems "just works". For example, I moved one older HD from a RAID1 to a standalone interface with no trouble. Even I wasn't sure that would work as I wasn't sure the RAID controller didn't borrow a little of the disk to record it's configuration.

In any case, I am not sure how the enclosures would be changing the actual hard drive format/sector size. These are usually set from the factory and require least a "quick format" (and I think in the past changing a jumper pin) by a manufacturer-specific tool. For example, this is what is required of a Seagate drive:

How to convert 512e to 4Kn using Fast Format (Seagate Exos X16 drive) ?

I'm planning to purchase some Seagate Exos X16 (model ST16000NM001G) 16TB drives. They come formatted in 512e by default, but they support "Fast Format" to convert to 4Kn so that they appear as a true 4Kn to the OS. This is documented in the Seagate documentation, but they neglect to say how you...

www.truenas.com

I would do the following in your case:
1. Confirm the drive(s) is actually in 512e or 4Kn mode by connecting it directly to a computerwith software of the manufacturer to confirm (may require Windows...maybe Linux)
2. Check if all USB<->SATA adapters preserve the drive's setting as-is, present it one way to the host regardless of the drive's setting, and/or are configurable (may require adapter-specific tool to modify)
3. Confirm the raw bytes on the disk are being presented to the host the same way through each adapter, etc

For 3, from the Terminal you can use "dd" to read and/or write specific ranges of the disk. Then use od or xxd to view as binary. For example something *like* this:

> dd if=/dev/rdisk2 of=first8k-test1a.raw bs=512 count=16
> dd if=/dev/rdisk2 of=first8k-test1b.raw bs=512 count=16
> od first8k-test1a.raw > first8k-test1a.od
> od first8k-test1b.raw > first8k-test1b.od
> diff first8k-test1a.od first8k-test1b.od

or your favorite tools to do the same...

 

[Dochartaigh]

I think you have a lot of variables running around here at the same time and that is confusing things. It appears you have drive format/sector size versus enclosures/chipsets versus versus filesystems/OS. I believe if the different enclosures present the underlying data to the OS the same way, they will be similarly readable.

Otherwise, generally moving drives among systems "just works". For example, I moved one older HD from a RAID1 to a standalone interface with no trouble. Even I wasn't sure that would work as I wasn't sure the RAID controller didn't borrow a little of the disk to record it's configuration.

In any case, I am not sure how the enclosures would be changing the actual hard drive format/sector size. These are usually set from the factory and require least a "quick format" (and I think in the past changing a jumper pin) by a manufacturer-specific tool. For example, this is what is required of a Seagate drive:

How to convert 512e to 4Kn using Fast Format (Seagate Exos X16 drive) ?

I'm planning to purchase some Seagate Exos X16 (model ST16000NM001G) 16TB drives. They come formatted in 512e by default, but they support "Fast Format" to convert to 4Kn so that they appear as a true 4Kn to the OS. This is documented in the Seagate documentation, but they neglect to say how you...

www.truenas.com

I would do the following in your case:
1. Confirm the drive(s) is actually in 512e or 4Kn mode by connecting it directly to a computerwith software of the manufacturer to confirm (may require Windows...maybe Linux)
2. Check if all USB<->SATA adapters preserve the drive's setting as-is, present it one way to the host regardless of the drive's setting, and/or are configurable (may require adapter-specific tool to modify)
3. Confirm the raw bytes on the disk are being presented to the host the same way through each adapter, etc

For 3, from the Terminal you can use "dd" to read and/or write specific ranges of the disk. Then use od or xxd to view as binary. For example something *like* this:

> dd if=/dev/rdisk2 of=first8k-test1a.raw bs=512 count=16
> dd if=/dev/rdisk2 of=first8k-test1b.raw bs=512 count=16
> od first8k-test1a.raw > first8k-test1a.od
> od first8k-test1b.raw > first8k-test1b.od
> diff first8k-test1a.od first8k-test1b.od

or your favorite tools to do the same...

Thanks. I don't have access to Linux (well, unless you count my Raspberry Pi with a butchered linux version I use to emulate old video games systems on...).

Also kinda know nothing about using the specialized manufacturers tools on HDD's... and would be worried about messing with something which could brick my kinda expensive HDD's... like I was reading (and this IS a Seagate drive btw) about that SeaChest program, and how sometimes (especially on a consumer Barracuda drive, i.e. not enterprise grade) when you change the sectors it can be NON-reversible, and even when you can reverse it, it'll commonly not reverse everything 100% and can brick some other features... so I don't think I'm willing to take that chance on a drive which is still $135 of hard earned cash...

BUT I CAN try the terminal code easy enough!

Now like I said, I'm a dummy with all this... so ChatGPT walked me through it, and this is the summary it gave me:


Update on Testing Different Enclosures with DD & Sector Formatting Issues:

I ran a series of tests using dd in Terminal to compare how the Plugable and Sabrent enclosures handle raw drive data. Here’s what I found:

• First Test: Formatted the drive in the Plugable → Ran dd dump → Moved it to Sabrent → dd failed, and the drive was unreadable.
• Second Test (Reverse Order): Formatted the drive in Sabrent → Ran dd dump → Moved it to Plugable → dd worked, but the drive was still unreadable in macOS.
• Diffing the data: Even when we successfully dumped data, macOS still failed to recognize the drive after switching enclosures.

Findings:​

1. The issue is NOT the raw data itself but how macOS interprets the partition structure between enclosures.
2. The Sabrent presents the drive with a 4K sector size, while the Plugable defaults to 512e. macOS doesn’t handle this switch well.
3. Once formatted in one enclosure, the drive becomes unreadable in the other, regardless of whether the raw data matches.
4. macOS won’t “fix” this by itself. Even wiping the first 8KB+ of data (zeroing out MBR/GPT) didn’t resolve the issue.

Conclusion & Next Steps:​

• Moving drives between enclosures is unreliable unless they have identical sector handling.
• At this point, the only workaround is to format the drive in the enclosure you plan to use long-term and not move it between different enclosures.

If anyone has insights on a way to force macOS to re-read the drive properly when switching enclosures, I'd love to hear it.

/end ChatGPT's spiel

 

[ChrisA]

And my only point is to get a foolproof offsite backup (i.e. networking/NAS won't help). You suggested I use a single enclosure with only one exact hard drive. What if that enclosure breaks? You then LOSE all your data - since there's NO guarantee you can buy that same exact model with that same chipset again

The backup system needs to be designed so that you can have the disk fail and the failure will be a non-issue because it is just one of several copies.

Saying "What if the enclosure fails?" is not different then saying "What if the drive fails". It WILL happen if you wait long enough.

They have lots of names for different backup sceems like "1, 2, 3" and so on. But what they all do is ensure that if one of the backup drives fails you still REDUNDENT copies. This is why you need at least THREE copies. Three is the minimum number

The best way to move a drive is to keep it inside an enclosure. You get some mechanical protection that way.

If you MUST move bare drives buy a Synology NAS and connect it to all your computers. Then periodically pull all the drives out of the NAS, pack them in a fire safe the drive the safe to some other place and bring the safe from that building home.

And even better method is if you have Internet at the offsite location, then you have the NAS at each location and tell them to continuously sync and use a versioned file system

But in every case, you have to design it so that if a backup copy fails, get burned in a fire, or stolen you don't need to care. This might mean a 1,2,3,4 system.

Also you might try "Back Blaze" or something like that. CLoud backup works well and is pretty foolproof. (No, they can't spy on your data, it is encrypted at your end.)

 

[Dochartaigh]

And just to update, tried a 3rd enclosure (the last I have left, or could find in my messy garage at least

This one is an old(ish) Lacie G-Drive (USB 3.0 at least, so not like super ancient) I had shucked the HDD out of. Lacie is also known to be VERY friendly with Mac's (kinda like OWC). I formatted the 8TB in the Plugable, and it worked in the Lacie. Formatted that drive in the LaCie, and the Plugable could read it. Of course nothing works in or out of the Sabrent, unless that Sabrent formats it itself (which also seems to happen in several of those other brands I mentioned, which I tried in the past and don't have anymore... and actually made posts about similar issues with those a couple years ago here as well, so this seems to be pretty common and is NOT just a problem in the Sabrent... at least we quasi-know the reason why now... kinda...).

So I'm literally going to throw the Sabrent away. I don't care if it's literally the BEST-SELLING 3.5" enclosure on all of Amazon - it's junk for my uses.

Going to probably give up on this endeavor and buy an OWC enclosure, if not several - they use a 13-year old chipset in their single enclosure, and a 9-year old chipset (JMicron JMS567 and JMicron JMS562) in their Mercury Elite Pro Dual... but at least seem to keep using similar chipsets in all of theirs, programmed/firmware'd the same way (I talked to them over tech support chat) with both 512e and 4kn compatibility (so like the Plugable, with similar specs, might actually also be able to read the internal drives out of my 2009 Mac Pro as well). Still not ideal because if these break 10 years down the line and I can't get a replacement with the same/super-similar chipset the drive may become unreadable... but it seems like the best I can do at the moment.

 

[Dochartaigh]

The backup system needs to be designed so that you can fave the disk fail and the fsilur will be a non-issue because it is just one of several copies.

Saying "what if the enclosure fails?" is not different then says "what if the drive fails". It WILL happen if you wait long enough.

They have lots of names for different backup sceems like "1, 2, 3" and so on. But what they all do is ensure that if one of the backup drives fail to still a REDUNDENT copies. This is why you need at least THREE copies. Three is the minimum number

The best way to move a drive is to keep it inside an enclosure. You get some mechanical protection that way.

If you MUST move bare drives buy a Synology NAS and connect it to all your computers. Then periodically pull all the drives out of the NAS, pack them in a fire safe the drive the safe to some other place and bring the safe from that building home.

And even better method is if you have Internet at the offsite location, then you have the NAS at each location and tell them to continuously sync and use a versioned file system

But in every case, you have to design it so that if a backup copy fails, get burned in a fire, or stolen you don't need to care. This might mean a 1,2,3,4 system.

Also you might try "Back Blaze" or something like that. CLoud backup works well and is pretty foolproof. (No, they can't spy on your data, it is encrypted at your end.)

Thank you, sincerely, but I think you're the 2nd (maybe 3rd) person to assume I don't have multiple backups. I do. I have 3x drives in the Mac Pro with redundant data. Backup drive in my safe in the same house. Another at my parents house. Plus cloud backup (Backblaze actually - like you mentioned).

That's off-topic though. In this topic I'm ONLY trying to figure out why a Mac-formatted HDD will NOT work in EVERY enclosure out there - like ALL my Windows-formatted drives seemingly can. Nothing more... just trying to figure out a solution for that which *I* like (NOT what other people think I should have or use enclosure-wise, not how many backups people think I should use, not how I should use a NAS instead... no offense, and thank you all very much for the contributions so far, but things like that simply aren't helpful to me - just trying to drill down and figure out that one single topic - which we kinda have an answer for the "why", but no solution to, sadly).

 

[bzgnyc2]

Thanks. I don't have access to Linux (well, unless you count my Raspberry Pi with a butchered linux version I use to emulate old video games systems on...).

Linux or Windows. Wasn't sure what you had handy. Most manufacturers make their low-level tools/diagnostics available for Windows and maybe Linux. Mac less so because Apple in many cases blocks low-level/direct access to a device.

Update on Testing Different Enclosures with DD & Sector Formatting Issues:

I ran a series of tests using dd in Terminal to compare how the Plugable and Sabrent enclosures handle raw drive data. Here’s what I found:

• First Test: Formatted the drive in the Plugable → Ran dd dump → Moved it to Sabrent → dd failed, and the drive was unreadable.

If dd from/to the drive fails when installed in the Sabrent, that is not a MacOS thing. That is a Sabrent thing. For whatever reason the Sabrent is requiring that it formats the drive.

• Second Test (Reverse Order): Formatted the drive in Sabrent → Ran dd dump → Moved it to Plugable → dd worked, but the drive was still unreadable in macOS.
• Diffing the data: Even when we successfully dumped data, macOS still failed to recognize the drive after switching enclosures.

As above, unclear what the Sabrent is doing. However, not clear to me from theabove whether the content retrieved by dd from the drive when connected to the Plugable is the same as what is read/written when connected through the Sabrent?

Findings:​

1. The issue is NOT the raw data itself but how macOS interprets the partition structure between enclosures.

That can't technically be true. The partition structure is stored on the drive. If macOS is getting a different partition structure depending on which enclosure is used then it is getting different raw data. Everything after that will fail.

1. The Sabrent presents the drive with a 4K sector size, while the Plugable defaults to 512e. macOS doesn’t handle this switch well.

What's unclear is what the drive's actual sector size is. As you noted above, changing drive sector sizes (e.g. switching between 4Kn and 512e) has risks and not something done casually. Yet each enclosure is presenting the same drive differently to the OS. It can't be instantly reformatting it. As such it makes no sense to me that the drive is actually being changed but rather the enclosure is doing some translation. In this case it is unclear which enclosure is doing the translation and the consequence of that translation on the data as presented back to macOS.

 

[Dochartaigh]

Linux or Windows. Wasn't sure what you had handy. Most manufacturers make their low-level tools/diagnostics available for Windows and maybe Linux. Mac less so because Apple in many cases blocks low-level/direct access to a device.



If dd from/to the drive fails when installed in the Sabrent, that is not a MacOS thing. That is a Sabrent thing. For whatever reason the Sabrent is requiring that it formats the drive.



As above, unclear what the Sabrent is doing. However, not clear to me from theabove whether the content retrieved by dd from the drive when connected to the Plugable is the same as what is read/written when connected through the Sabrent?



That can't technically be true. The partition structure is stored on the drive. If macOS is getting a different partition structure depending on which enclosure is used then it is getting different raw data. Everything after that will fail.



What's unclear is what the drive's actual sector size is. As you noted above, changing drive sector sizes (e.g. switching between 4Kn and 512e) has risks and not something done casually. Yet each enclosure is presenting the same drive differently to the OS. It can't be instantly reformatting it. As such it makes no sense to me that the drive is actually being changed but rather the enclosure is doing some translation. In this case it is unclear which enclosure is doing the translation and the consequence of that translation on the data as presented back to macOS.

So I again have to default to what ChatGPT tells me to reply to you in the detail you need - and as I now feel like I'm the intermediary between this post and my ChatGPT overlord, I won't hold it against you if you don't feel like replying lol (all the answers seem to be in the below copy and paste though! - and is what I saw in real-time as I was doing all this testing over Terminal which ChatGPT led me through).

I also DID purchase that dual-drive OWC HDD enclosure earlier today - so essentially giving up on this (although I would love love LOVE to get to the bottom of this still, as it's plagued me for more than a decade!!!) - and will just use an enclosure and no more bare HDD's in my own house (although I'll still store bare HDD's at my parents house who have limited space in their small fireproof safe -in little padded anti-static boxes- which will be pulled from that same OWC enclosure so I know they can be read later on).

I'm more than happy running any more tests you want, or pasting in the results if I ran them before. Here's the copy and paste from ChatGPT:


Thanks for the insights. Here’s what I can clarify based on our tests:

1. Sabrent vs. Plugable Sector Size Handling:
   • The Sabrent forces a 4K sector size (4096 bytes).
   • The Plugable presents the drive as 512-byte sectors (512e).
   • The drive itself is factory 512e but is being interpreted differently depending on the enclosure.
2. dd Read/Write Differences:
   • When formatted in the Plugable, dd works fine in the Plugable, but fails in the Sabrent.
   • When formatted in the Sabrent, dd works in the Sabrent, but while Plugable could dump data [and it matches 100%], macOS couldn't recognize the drive.
   • This suggests the enclosures are presenting different raw sector alignments, causing macOS to misinterpret the partition structure.
3. Partition Structure & Raw Data:
   • I agree that if macOS sees different partition structures depending on the enclosure, then something at the raw data level is different.
   • This aligns with the theory that one of the enclosures (likely the Sabrent) is forcing sector translation at a hardware level.
4. LaCie Enclosure Test – More Evidence Against Sabrent:
   • Today, I tested a LaCie G-Drive enclosure, which is known to be Mac-friendly.
   • A drive formatted in the Plugable was instantly recognized in the LaCie with no issues [and vice-versa].
   • This further suggests that enclosures like Plugable and LaCie do not modify sector sizes, while the Sabrent (and other enclosures I’ve used with this same behavior in the past) are forcing sector changes.
5. Enclosure Behavior:
   • The Plugable and LaCie enclosures do not modify the drive’s sector formatting, meaning they present the disk as-is.
   • The Sabrent forces a 4K sector size, which appears to break compatibility when moving between enclosures.
   • The fact that moving between enclosures results in an unreadable drive suggests that macOS does not handle sector size mismatches well.
6. Next Steps?
   • The missing piece is whether macOS itself can handle a drive that changes sector sizes depending on the enclosure.
   • If this is purely an enclosure-level translation issue, then any enclosure that doesn’t modify sector size should work consistently.

 

[folmerw]

Thank you so much for posting this! I was actually having the exact same problem with an old Seagate drive I had shucked from its enclosure, and was putting in a ProBox SATA enclosure, and then getting the dreaded “this drive can’t be read, do you want to initialize?” prompt on both my iMac 2017 and my MacBook Air 2014…

But then reading this, I thought maybe I was just facing the same issue as yourself? And so I put it back into the old Seagate enclosure I had shucked it out of, and sure enough, it’s able to be read from flawlessly!

Before your posts, I was sure that I would have to shell out for something like Disk Drill or something to get my material off of it, which has some pretty sketch reviews, but was the only way I could see my material on it, despite it not being mountable… So your posts saved me a lot of money on that!

But sorry I can’t help you myself, other than to say I think you must be right about certain drives can ONLY be read from in the ORIGINAL enclosure that they came in…

 

[Dochartaigh]

Thank you so much for posting this! I was actually having the exact same problem with an old Seagate drive I had shucked from its enclosure, and was putting in a ProBox SATA enclosure, and then getting the dreaded “this drive can’t be read, do you want to initialize?” prompt on both my iMac 2017 and my MacBook Air 2014…

But then reading this, I thought maybe I was just facing the same issue as yourself? And so I put it back into the old Seagate enclosure I had shucked it out of, and sure enough, it’s able to be read from flawlessly!

Before your posts, I was sure that I would have to shell out for something like Disk Drill or something to get my material off of it, which has some pretty sketch reviews, but was the only way I could see my material on it, despite it not being mountable… So your posts saved me a lot of money on that!

But sorry I can’t help you myself, other than to say I think you must be right about certain drives can ONLY be read from in the ORIGINAL enclosure that they came in…

I'm glad this info is helping somebody else, and glad yours worked out!

The only thing I would like to further test is if all of these non-standard enclosures, like my buggy Sabrent one (which seems to force sector changes), are buggy in the same way... i.e. if I format a drive on the Sabrent (which then won't be able to be read in my Plugable, Lacie, and new OWC Dual enclosures which do NOT force sector changes), if that hard drive WILL work in one of these other non-standard/bad enclosures like I've owned over the years... but I've given all those away (or can't find them at the moment) to test. If this proves to be true, it would be a workaround for somebody who lost or broke their Sabrent and still needs to read that data (where they would have to re-purchase the same messed-up Sabrent enclosure again to be able to recover that data).

 

[bzgnyc2]

Thank you so much for posting this! I was actually having the exact same problem with an old Seagate drive I had shucked from its enclosure, and was putting in a ProBox SATA enclosure, and then getting the dreaded “this drive can’t be read, do you want to initialize?” prompt on both my iMac 2017 and my MacBook Air 2014…

But then reading this, I thought maybe I was just facing the same issue as yourself? And so I put it back into the old Seagate enclosure I had shucked it out of, and sure enough, it’s able to be read from flawlessly!

Before your posts, I was sure that I would have to shell out for something like Disk Drill or something to get my material off of it, which has some pretty sketch reviews, but was the only way I could see my material on it, despite it not being mountable… So your posts saved me a lot of money on that!

But sorry I can’t help you myself, other than to say I think you must be right about certain drives can ONLY be read from in the ORIGINAL enclosure that they came in…

It is possible that an enclosure manufacturer -- especially the ones that sell as a bundled solution rather than a component -- ties any bundled drive to the enclosure or otherwise employs custom firmware limiting its usability outside that brand of enclosure/intended use case.

I generally haven't seen that with standalone drives and enclosures. My experience in those cases has been that the drive can be moved internal to external and enclosure to enclosure. I am not saying none exist though I would consider such enclosures fundamentally flawed. This is a good reminder of one of the reasons why I don't generally buy packaged drives/enclosures (previously HDD and now the same with NVMe SSD).