APFS vs External Samsung T3

maflynn

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May 3, 2009
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Well, I finally bit the bullet and upgraded to High Sierra after feeling pretty good that I accounted for all of the risks regarding compatibility.

Upgrade went fine, except that it seems my Samsung T3 SSD is not compatible with APFS :( This was one of the major reasons for my upgrading, and so because of that. I'm somewhat bummed out.

There was no upgrade APFS checkbox on the initial upgrade, the option is grayed out in the Disk Utility regardless if I boot up in Recovery partition or just normal boot

I was expecting, that given the popularity of this SSD, that it would be compatible. I guess I assumed wrong.
 

SoCalReviews

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This reply was edited (removed) per OP suggestion that it was off topic.
 
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bcaslis

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Mar 11, 2008
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I was able to format my T3 to APFS. However you need to do it from the Disk Utility edit menu (convert to APFS). However I can't convert a Samsung T5 I just bought to APFS, the conversion fails. I'm very confused about what is going on.
 

neliason

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Oct 1, 2015
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However I can't convert a Samsung T5 I just bought to APFS, the conversion fails. I'm very confused about what is going on.
I’ve got a T5 I run my virtual machines from that I want to convert. I’ll hold off now.

Does failure to convert leave the drive as it was? Based on how I understand the conversion works it seems like a failed conversion should be non destructive, but I wanted to verify that from your experience.

These are popular drives. The fact they won’t convert isn’t giving me confidence in APFS or Apple.
 

maflynn

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I was able to format my T3 to APFS. However you need to do it from the Disk Utility edit menu (convert to APFS). However I can't convert a Samsung T5 I just bought to APFS, the conversion fails. I'm very confused about what is going on.
That's greyed out as I mentioned in my OP, both when I boot into the T3 and also when I use the recovery partition.
[doublepost=1506692871][/doublepost]
It may not have much to do with the T3 specifically since you may get it to work but what I am pointing out is how the companies are trying to control how you store and access your own data.
That has nothing to do with the subject and I would appreciate if the thread wasn't derailed. If you want to discuss that, then I recommend starting your thread.
 

SoCalReviews

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Dec 31, 2012
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That's greyed out as I mentioned in my OP, both when I boot into the T3 and also when I use the recovery partition.
[doublepost=1506692871][/doublepost]
That has nothing to do with the subject and I would appreciate if the thread wasn't derailed. If you want to discuss that, then I recommend starting your thread.
I understand. You only want replies relating to technical support from other forum members for your issue and nothing else. I'll edit my replies to minimum then if that helps. It was not my intention to "derail" your thread.
 
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bcaslis

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Mar 11, 2008
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That's greyed out as I mentioned in my OP, both when I boot into the T3 and also when I use the recovery partition.
[doublepost=1506692871][/doublepost]
That has nothing to do with the subject and I would appreciate if the thread wasn't derailed. If you want to discuss that, then I recommend starting your thread.
I boot to the internal SSD and then run Disk Utility and the menu is not greyed out. I would try that.
[doublepost=1506698895][/doublepost]
I’ve got a T5 I run my virtual machines from that I want to convert. I’ll hold off now.

Does failure to convert leave the drive as it was? Based on how I understand the conversion works it seems like a failed conversion should be non destructive, but I wanted to verify that from your experience.

These are popular drives. The fact they won’t convert isn’t giving me confidence in APFS or Apple.
Failure leaves it as is.
 

fredou

macrumors newbie
May 21, 2011
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However I can't convert a Samsung T5 I just bought to APFS, the conversion fails. I'm very confused about what is going on.
You have to do it with terminal. I wasn't able to do it with Diskutil GUI as it always failed. The main reason is because the drive is using scheme MBR instead of GPT. And the partition menu at the top is greyed in Diskutil GUI. So I did it with terminal:

diskutil list
(note the disk number of Samsung T5)
diskutil partitionDisk /dev/disk# GPT JHFS+ New 0b

Then I used the Diskutil GUI for converting to APFS. It worked perfectly!

BEWARE, YOU WILL LOOSE ALL FILES FROM DISK DOING THE ABOVE COMMANDS.
 

bcaslis

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Mar 11, 2008
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You have to do it with terminal. I wasn't able to do it with Diskutil GUI as it always failed. The main reason is because the drive is using scheme MBR instead of GPT. And the partition menu at the top is greyed in Diskutil GUI. So I did it with terminal:

diskutil list
(note the disk number of Samsung T5)
diskutil partitionDisk /dev/disk# GPT JHFS+ New 0b

Then I used the Diskutil GUI for converting to APFS. It worked perfectly!

BEWARE, YOU WILL LOOSE ALL FILES FROM DISK DOING THE ABOVE COMMANDS.
Interesting. I wonder why partitioning from the GUI is greyed out. I will give this a try tonight.
 

user1234

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Mar 3, 2009
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You have to do it with terminal. I wasn't able to do it with Diskutil GUI as it always failed. The main reason is because the drive is using scheme MBR instead of GPT. And the partition menu at the top is greyed in Diskutil GUI. So I did it with terminal:

diskutil list
(note the disk number of Samsung T5)
diskutil partitionDisk /dev/disk# GPT JHFS+ New 0b

Then I used the Diskutil GUI for converting to APFS. It worked perfectly!

BEWARE, YOU WILL LOOSE ALL FILES FROM DISK DOING THE ABOVE COMMANDS.
I can confirm that this works. Did it a couple of days ago on my T5.
 

upandown

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Apr 10, 2017
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Using Apples Disc Utilies I had to convert my EVO 850 to something other than APFS first, ex. fat-32. And then was able to convert to APFS. Otherwise it was grayed out for me too. Might be another trick
 
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maflynn

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May 3, 2009
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I boot to the internal SSD and then run Disk Utility and the menu is not greyed out. I would try that.
I cloned my T3 disk to a backup spinning disk, and then booted that up. No dice, still greyed out.

So I did it with terminal:

diskutil list
(note the disk number of Samsung T5)
diskutil partitionDisk /dev/disk# GPT JHFS+ New 0b
I may tried that, but tbh, I'd rather look for a non-destructive option, but given that I just cloned my drive, I'll not lose data, just time to restore it.
 

bcaslis

macrumors 68020
Mar 11, 2008
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You have to do it with terminal. I wasn't able to do it with Diskutil GUI as it always failed. The main reason is because the drive is using scheme MBR instead of GPT. And the partition menu at the top is greyed in Diskutil GUI. So I did it with terminal:

diskutil list
(note the disk number of Samsung T5)
diskutil partitionDisk /dev/disk# GPT JHFS+ New 0b

Then I used the Diskutil GUI for converting to APFS. It worked perfectly!

BEWARE, YOU WILL LOOSE ALL FILES FROM DISK DOING THE ABOVE COMMANDS.
Actually, I connected the drive to a Mac running Sierra and was able to partition it so it was using GUID. Then plugged it into a High Sierra machine and was able to convert the T5 to APFS. Seems like Disk Utility has lost functionality in High Sierra. There doesn't seem like any good reason for this.
 

Mike Boreham

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Aug 10, 2006
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I booted from a bootable USB installer, and was able to format my Samsung T3 as APFS using Disk Utility, then install 10.13 onto it, then migrate.

Depending what state the T3 is in after previous attempts you might need to use diskutil from Terminal instead of regular Disk Utility, as it can do things Disk Utility can't.

BTW for anyone who has not discovered it, the free Boot Buddy is hands down the easiest way to create a boot installer. (I have no connection etc etc).

EDIT My experience of converting to APFS form the Disk Utility Edit menu after install has not been successful.
 

Fishrrman

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Feb 20, 2009
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Frankly, I don't understand "the stampede" by everyone to convert to APFS.

Is it the compulsion to have "the latest and greatest" (and the "untested" as well)...?

I'm sticking with HFS+ -- a proven and reliable file system -- until I absolutely have no choice.

And just because Apple tries to "force convert" you -- you STILL "have a choice", IF you know what to do...
 
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upandown

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Apr 10, 2017
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Frankly, I don't understand "the stampede" by everyone to convert to APFS.

Is it the compulsion to have "the latest and greatest" (and the "untested" as well)...?

I'm sticking with HFS+ -- a proven and reliable file system -- until I absolutely have no choice.

And just because Apple tries to "force convert" you -- you STILL "have a choice", IF you know what to do...
You do realize you're the other extreme right?

And to answer your question, it's believed to be better for SSD operations. A homogeneous relationship =)
 
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Awgd8

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Sep 23, 2014
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WI
I have a new Samsung T5 500Gig
and a Mid 2017 iMac 27” 5k with 1TB fusion drive.

Everything is working fine on APFS for both drive.

What I did first is I upgraded my iMac hard drive to High Sierra OS (though the file system did not convert automatically to APFS.

Then using the High Sierra OS on the iMac drive, I used the Disk utilities and format the T5 SSD external to APFS file.
Installed the Mac OS high Sierra to the T5. Then booted the MacOS from T5 and then reformated my IMac 1TB fusion to APFS.
 
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user1234

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Mar 3, 2009
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Sweden
Frankly, I don't understand "the stampede" by everyone to convert to APFS.

Is it the compulsion to have "the latest and greatest" (and the "untested" as well)...?

I'm sticking with HFS+ -- a proven and reliable file system -- until I absolutely have no choice.

And just because Apple tries to "force convert" you -- you STILL "have a choice", IF you know what to do...
It has A LOT of benefits over HFS+. It's a modern filesystem with copy on write, snapshots, volumes that share common space (no hard limits of partitions) and on and on. It's also much better optimized for SSD. I've been waiting for this for a long time.

Of course I back up to other solutions with other tried and true file systems, because AFPS is still new and hasn't proven itself over time like some of the other ones have, but it's been live for over a year on iOS and no major issues so far. I feel pretty confident about using it. The important part is BACKUP! Seriously. No excuses not to have backups of anything important.
 

AlexH

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Mar 7, 2006
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Frankly, I don't understand "the stampede" by everyone to convert to APFS.

Is it the compulsion to have "the latest and greatest" (and the "untested" as well)...?

I'm sticking with HFS+ -- a proven and reliable file system -- until I absolutely have no choice.

And just because Apple tries to "force convert" you -- you STILL "have a choice", IF you know what to do...
I’m with you, mostly. I do hope to upgrade to APFS eventually, but once the majority of bugs have been ironed out. I’m probably going to skip High Sierra altogether and catch the next MacOS release.