Cannot decrease Windows partition size to less than 1058 GB

Question

Cannot decrease Windows partition size to less than 1058 GB

OS: macOS Sierra, Version 10.12.6

Model: iMac (27-inch, Late 2012)

Processor: 3.4 GHz Intel Core i7

Memory: 16 GB 1600 MHz DDR3

Startup Disk Storage: 3.11 TB

Graphics: NVIDIA GeForce GTX 680MX 2048 MB

Boot Camp Assistant: Version 6.1.0 (6050.60.1)

I have already created an install disk and downloaded the latest Windows support software, but I have a problem when I try to add a Windows partition to the startup disk. The slider bar does not allow me to make the partition any smaller than 1058 GB, which I know for a fact is WAY more than you need for a partition. Also, I only have about 313 GB available on my startup disk, so I couldn't set up a partition with a size this big, anyway, so why is it asking me to do so? I know the problem isn't in the ISO image or the version of Windows I'm trying to install; I tried two different ISO files (one for Windows 8.1, and one for Windows 10) and they both had this problem. In the image below, the divider on the slider bar is dragged as far to the right as possible.

I believe the problem is in Boot Camp Assistant itself, because this slider bar seems really, really broken, and not just because of the 1058 GB minimum. For example, when you drag the divider, the partition sizes don't increase/decrease by increments of 1 GB. Rather, the size will apparently not change, then suddenly jump by a large amount (e.g. from 1058 GB to 3106 GB, or from 3106 GB to 5153 GB, as shown in the next four images. At this point, the partition size would be larger than the amount of storage in the entire startup disk).

I can even drag the divider of the slider bar so far to the left that it leaves the window.

With all of this, I think it's safe to say that the application itself is pretty broken. Is there any way to uninstall, then reinstall Boot Camp Assistant without completely reinstalling macOS? Or is there another solution that you guys suggest? I included some tech specs at the top if any of those help.

Final note: I haven't actually tried to install the partition, because if it was successful, and the size of the partition was as big as Boot Camp Assistant says it is, there would obviously be no room for over 500 GB of the files in the Mac partition.

iMac, macOS Sierra (10.12.6), null

Posted on Nov 11, 2017 2:58 PM

Reply

Answer 1

Loner T

Level 9

59,471 points

Nov 11, 2017 6:03 PM in response to CourtOfTheCrimsonKing

Your CS looks fine. Please remove the 4TB disk3 and connect it only after Windows is fully installed.

Run

How to reset the System Management Controller (SMC) on your Mac - Apple Support

How to reset NVRAM on your Mac - Apple Support

What is the version of Windows you want to install?

Reply

Answer 2

Loner T

Level 9

59,471 points

Nov 12, 2017 12:06 PM in response to CourtOfTheCrimsonKing

Are you typing the command on a single line? Can you show me what is exactly typed in Terminal?

diskutil cs resizeStack A73082BE-C450-44D6-BE6D-92C37182E7AE 015DDA11-E6C3-411A-A094-8F59D7B75797 1800G fat32 BOOTCAMP 100g jhfs+ REMAINDER 0g

OR

diskutil cs resizeStack A73082BE-C450-44D6-BE6D-92C37182E7AE1800G fat32 BOOTCAMP 100g jhfs+ REMAINDER 0g

Also see Re: Can't create Windows partition on roll-your-own Fusion drive .

Reply

Answer 3

Loner T

Level 9

59,471 points

Nov 12, 2017 6:09 PM in response to CourtOfTheCrimsonKing

If you have an external 4TB disk which is blank, you can directly attach it to the iMac, run a TM backup now.

Once you have a backup, we can erase the internal drive, re-partition it so your 300GB free space is located in the appropriate 'sandwich' layout, and then restore the TM backup across a CoreStorage volume which has three chunks, instead of the current two (SSD and HDD). This will be the same end state, as if you have a 300GB chunk available within the first 2TB of the disk.

The second option is to create a 300GB chunk at the beginning of the HDD, and then have the SSD+remaining 2+ TB HDD part in a 2-part CS volume.

The end state is to try and get a chunk for BC partition within the first 2TB of the HDD.

There is a third option that I use on my MacMinis. I use the SSD (in my case it is 256GB or 512GB SSD) in two parts. One part is used for a macOS CS part, the other houses only the base Windows OS. I split the HDD into two parts, and combine the macOS SSD + one half of HDD as a CS volume for macOS, and leave the remainder of the HDD for a D: drive to store documents for Windows.

Of all three options, the 'sandwich' is the Apple standard, while the other two are non-standard. If you want to see some of the tests, they are documented in OSX and Bootcamp discussion .

This is from a Mini with a 256GB SSD/1TB HDD. On this one, I do not use a separate Windows D:.

diskutil list

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *256.1 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_CoreStorage 128.0 GB disk0s2

3: Apple_Boot Boot OS X 134.2 MB disk0s3

4: Microsoft Basic Data BOOTCAMP 127.7 GB disk0s4

/dev/disk1

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk1

1: EFI EFI 209.7 MB disk1s1

2: Apple_CoreStorage 999.3 GB disk1s2

3: Apple_Boot Boot OS X 650.0 MB disk1s3

/dev/disk2

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS OSX-FusionHD *1.1 TB disk2

diskutil cs list

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group DF140929-90E7-48E1-AC3D-C9C75BA88D1D

=========================================================

Name: OSX-FusionHD

Status: Online

Size: 1127375384576 B (1.1 TB)

Free Space: 69632 B (69.6 KB)

|

+-< Physical Volume C856A74C-EB57-4D1F-8223-0A22215218ED

| ----------------------------------------------------

| Index: 0

| Disk: disk0s2

| Status: Online

| Size: 128030257152 B (128.0 GB)

|

+-< Physical Volume 80D91A14-CCC9-47B1-B071-B9ADFF23924F

| ----------------------------------------------------

| Index: 1

| Disk: disk1s2

| Status: Online

| Size: 999345127424 B (999.3 GB)

|

+-> Logical Volume Family 019D610F-21AC-4B54-AB0A-6D5F90D520A7

----------------------------------------------------------

Encryption Status: Unlocked

Encryption Type: None

Conversion Status: NoConversion

Conversion Direction: -none-

Has Encrypted Extents: No

Fully Secure: No

Passphrase Required: No

|

+-> Logical Volume D9DC0F70-38C7-4AE6-BAC4-CFBE0F8D4F68

---------------------------------------------------

Disk: disk2

Status: Online

Size (Total): 1118844862464 B (1.1 TB)

Conversion Progress: -none-

Revertible: No

LV Name: OSX-FusionHD

Volume Name: OSX-FusionHD

Content Hint: Apple_HFS

diskutil info disk0

Device Identifier: disk0

Device Node: /dev/disk0

Part of Whole: disk0

Device / Media Name: Samsung SSD 840 PRO Series Media

Volume Name: Not applicable (no file system)

Mounted: Not applicable (no file system)

File System: None

Content (IOContent): GUID_partition_scheme

OS Can Be Installed: No

Media Type: Generic

Protocol: SATA

SMART Status: Verified

Total Size: 256.1 GB (256060514304 Bytes) (exactly 500118192 512-Byte-Units)

Volume Free Space: Not applicable (no file system)

Device Block Size: 512 Bytes

Read-Only Media: No

Read-Only Volume: Not applicable (no file system)

Ejectable: No

Whole: Yes

Internal: Yes

Solid State: Yes

OS 9 Drivers: No

Low Level Format: Not supported

Device Location: "Lower"

diskutil info disk1

Device Identifier: disk1

Device Node: /dev/disk1

Part of Whole: disk1

Device / Media Name: Hitachi HTS541010A9E680 Media

Volume Name: Not applicable (no file system)

Mounted: Not applicable (no file system)

File System: None

Content (IOContent): GUID_partition_scheme

OS Can Be Installed: No

Media Type: Generic

Protocol: SATA

SMART Status: Verified

Total Size: 1.0 TB (1000204886016 Bytes) (exactly 1953525168 512-Byte-Units)

Volume Free Space: Not applicable (no file system)

Device Block Size: 512 Bytes

Read-Only Media: No

Read-Only Volume: Not applicable (no file system)

Ejectable: No

Whole: Yes

Internal: Yes

Solid State: No

OS 9 Drivers: No

Low Level Format: Not supported

Device Location: "Upper"

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Answer 4

Loner T

Level 9

59,471 points

Nov 15, 2017 3:20 AM in response to CourtOfTheCrimsonKing

Please do not delete backups. Time Machine backups are cumulative. If you click on Enter Time Machine selection in the Menu bar under the Time Machine icon, you can see a Time Line of your backups. See How to use Time Machine to back up or restore your Mac - Apple Support for an example.

As long as you have TM configured and have regular backups, you are fine. Can you boot into Internet Recovery? We will need to erase/partition the internal disks, so we can create a FAT32 partition in the first 2TB of the HDD.

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Answer 5

Loner T

Level 9

59,471 points

Nov 12, 2017 10:01 AM in response to CourtOfTheCrimsonKing

The EE entry is a Protective MBR for utilities that do not understand GPT. It is sized 4294967294 512-byte sectors, which is exactly 2TiB (multiples of 2**10).

On a 3TB disk, you either

must have a >= 1TB Windows partition, or,
a 'sandwich' layout for a <1TB layout where Windows is in the middle of two macOS slices on a CoreStorage volume.

There is a command called resizeStack (type diskutil cs resizeStack in Terminal and you will see the syntax and help), which can be used to create the 'sandwich' layout. If you can specify the size you want, I can give you commands for either layout to test.

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Answer 6

Nov 11, 2017 5:45 PM in response to Loner T

From diskutil list

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *121.3 GB
disk0

1: EFI EFI 209.7 MB
disk0s1

2: Apple_CoreStorage Macintosh HD 121.0 GB
disk0s2

3: Apple_Boot Boot OS X 134.2 MB
disk0s3

/dev/disk1 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *3.0 TB disk1

1: EFI EFI 209.7 MB
disk1s1

2: Apple_CoreStorage Macintosh HD 3.0 TB disk1s2

3: Apple_Boot Recovery HD 650.0 MB
disk1s3

/dev/disk2 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD +3.1 TB disk2

Logical Volume on disk0s2, disk1s2

A73082BE-C450-44D6-BE6D-92C37182E7AE

Unencrypted Fusion Drive

/dev/disk3 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *4.0 TB disk3

1: EFI EFI 314.6 MB
disk3s1

2: Apple_HFS My Book 4.0 TB disk3s2

/dev/disk4 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: FDisk_partition_scheme *32.0 GB disk4

1: DOS_FAT_32 WININSTALL 32.0 GB disk4s1

/dev/disk5 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: IR5_CCSA_X64FRE_EN-... +4.3 GB disk5

/dev/disk6 (disk image):

#: TYPE NAME SIZE IDENTIFIER

0: Boot Camp +2.8 GB disk6

From diskutil cs list

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group AF994E04-C4E9-4B5E-AA2F-358D14EE484A

=========================================================

Name: Macintosh HD

Status: Online

Size: 3120722075648 B (3.1 TB)

Free Space:
114688 B (114.7 KB)

|

+-< Physical Volume 2A17E9A7-66D9-4813-AC93-055254F1C190

|
----------------------------------------------------

|
Index: 0

|
Disk: disk0s2

|
Status:
Online

|
Size: 120988852224 B (121.0 GB)

|

+-< Physical Volume 015DDA11-E6C3-411A-A094-8F59D7B75797

|
----------------------------------------------------

|
Index: 1

|
Disk: disk1s2

|
Status:
Online

|
Size: 2999733223424 B (3.0 TB)

|

+-> Logical Volume Family 1D90F443-DCF7-41E9-8FA3-81E8542FA48F

----------------------------------------------------------

Encryption Type: None

|

+-> Logical Volume A73082BE-C450-44D6-BE6D-92C37182E7AE

---------------------------------------------------

Disk: disk2

Status: Online

Size (Total): 3106191572992 B (3.1 TB)

Revertible: No

LV Name: Macintosh HD

Volume Name: Macintosh HD

Content Hint: Apple_HFS

LVG Type: Fusion, Sparse

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Answer 7

Nov 11, 2017 6:51 PM in response to Loner T

I want to install Windows 10. I used the ISO file provided by the official Microsoft website to make the install disk. When I got the error, I used an ISO file for Windows 8.1 instead (also provided by the Microsoft website), but I got the same error. I would prefer Windows 10, and, as previously mentioned, I'm pretty sure the OS version isn't the problem here.

Also, none of the instructions that you gave me worked. I removed disk3 (that's just used for Time Machine backups) and I followed the instructions of those two articles, but the slider bar remains the same.

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Answer 8

Nov 11, 2017 7:27 PM in response to Loner T

Started partition map repair on disk0

Checking prerequisites

Checking the partition list

Adjusting partition map to fit whole disk as required

Checking for an EFI system partition

Checking the EFI system partition's size

Checking the EFI system partition's file system

Checking the EFI system partition's folder content

Checking all HFS data partition loader spaces

Checking booter partitions

Checking booter partition disk0s3

Verifying file system

Checking Journaled HFS Plus volume

Checking extents overflow file

Checking catalog file

Checking multi-linked files

Checking catalog hierarchy

Checking extended attributes file

Checking volume bitmap

Checking volume information

The volume Boot OS X appears to be OK

File system check exit code is 0

Reviewing boot support loaders

Checking Core Storage Physical Volume partitions

Verifying storage system

Checking volume

disk1s2: Scan for Volume Headers

disk0s2: Scan for Volume Headers

disk1s2: Scan for Disk Labels

disk0s2: Scan for Disk Labels

Logical Volume Group AF994E04-C4E9-4B5E-AA2F-358D14EE484A spans 2 devices

disk0s2+disk1s2: Scan for Metadata Volume

Logical Volume Group has a 4481 MB Metadata Volume with double redundancy

Start scanning metadata for a valid checkpoint

Load and verify Segment Headers

Load and verify Checkpoint Payload

Load and verify Transaction Segment

Incorporate 5 newer non-checkpoint transactions

Load and verify Virtual Address Table

Load and verify Segment Usage Table

Load and verify Metadata Superblock

Load and verify Logical Volumes B-Trees

Logical Volume Group contains 1 Logical Volume

Load and verify 1D90F443-DCF7-41E9-8FA3-81E8542FA48F

Load and verify A73082BE-C450-44D6-BE6D-92C37182E7AE

Load and verify Freespace Summary

Load and verify Block Accounting

Load and verify Live Virtual Addresses

Newest transaction commit checkpoint is valid

Load and verify Segment Cleaning

The volume AF994E04-C4E9-4B5E-AA2F-358D14EE484A appears to be OK

Storage system check exit code is 0

Repairing storage system

The volume disk1s2+disk0s2 cannot be repaired when it is in use

Checking volume

disk1s2: Scan for Volume Headers

disk0s2: Scan for Volume Headers

disk1s2: Scan for Disk Labels

disk0s2: Scan for Disk Labels

Logical Volume Group AF994E04-C4E9-4B5E-AA2F-358D14EE484A spans 2 devices

disk0s2+disk1s2: Scan for Metadata Volume

Logical Volume Group has a 4481 MB Metadata Volume with double redundancy

Start scanning metadata for a valid checkpoint

Load and verify Segment Headers

Load and verify Checkpoint Payload

Load and verify Transaction Segment

Incorporate 6 newer non-checkpoint transactions

Load and verify Virtual Address Table

Load and verify Segment Usage Table

Load and verify Metadata Superblock

Load and verify Logical Volumes B-Trees

Logical Volume Group contains 1 Logical Volume

Load and verify 1D90F443-DCF7-41E9-8FA3-81E8542FA48F

Load and verify A73082BE-C450-44D6-BE6D-92C37182E7AE

Load and verify Freespace Summary

Load and verify Block Accounting

Load and verify Live Virtual Addresses

Newest transaction commit checkpoint is valid

Load and verify Segment Cleaning

The volume AF994E04-C4E9-4B5E-AA2F-358D14EE484A appears to be OK

Storage system check exit code is 0

Updating Windows boot.ini files as required

The partition map appears to be OK

Finished partition map repair on disk0

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Answer 9

Loner T

Level 9

59,471 points

Nov 12, 2017 4:45 AM in response to CourtOfTheCrimsonKing

The point of the exercise is to validate if DU gives the same errors as does BCA, to decide which one is at fault. If DU works and you were able to create a partition of the size of you want without any issues, then it can be used as a destination for the Windows installation with some additional steps to create a MBR for BIOS support.

Can you post the output of

diskutil list

for validation of the FAT partition?

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Answer 10

Nov 12, 2017 8:36 AM in response to Loner T

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *121.3 GB
disk0

1: EFI EFI 209.7 MB
disk0s1

2: Apple_CoreStorage Macintosh HD 121.0 GB
disk0s2

3: Apple_Boot Boot OS X 134.2 MB
disk0s3

/dev/disk1 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *3.0 TB disk1

1: EFI EFI 209.7 MB
disk1s1

2: Apple_CoreStorage Macintosh HD 2.9 TB disk1s2

3: Apple_Boot Recovery HD 650.0 MB
disk1s3

4: Microsoft Basic Data B C P 89.5 GB disk1s4

/dev/disk2 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD +3.0 TB disk2

Logical Volume on disk0s2, disk1s2

A73082BE-C450-44D6-BE6D-92C37182E7AE

Unencrypted Fusion Drive

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Answer 11

Loner T

Level 9

59,471 points

Nov 12, 2017 8:50 AM in response to CourtOfTheCrimsonKing

The hybrid MBR needed on a 2012 iMac for legacy BIOS cannot accommodate a BC partition which starts outside the 2TB address and is less than 1TB. Can you post the output of

sudo fdisk /dev/disk1

BTW, I assume you have heard - King Crimson In The Court Of The Crimson King live - YouTube .

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Answer 12

Nov 12, 2017 9:28 AM in response to Loner T

Disk: /dev/disk1 geometry: 97451/255/63 [1565565872 sectors]

Signature: 0xAA55

Starting Ending

#: id
cyl
hd sec -
cyl
hd sec [ start - size]

------------------------------------------------------------------------

1: EE 1023 254
63 - 1023 254
63 [ 1 - 4294967294] <Unknown ID>

2: 00 0
0
0 - 0
0
0 [ 0 - 0] unused

3: 00 0
0
0 - 0
0
0 [ 0 - 0] unused

4: 00 0
0
0 - 0
0
0 [ 0 - 0] unused

Also, yeah, that's why I chose the name. King Crimson is one of my favorites. I haven't heard this live version until now, though.

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Answer 13

Loner T

Level 9

59,471 points

Nov 12, 2017 10:32 AM in response to CourtOfTheCrimsonKing

Since you need a 'sandwich' layout, remove the current partition using Disk Utility, and run

diskutil cs resizeStack A73082BE-C450-44D6-BE6D-92C37182E7AE 015DDA11-E6C3-411A-A094-8F59D7B75797 1800G fat32 BOOTCAMP 100g jhfs+ REMAINDER 0g

This command reduces the current 'Macintosh HD' to 1800G, creates a 100g FAT32 partition within the first 2TB of the HDD (we choose the HDD physical volume UUID which is the second UUID in the command). The remaining space becomes jhfs+ called 'REMAINDER'.

If this completes successfully, REMAINDER can be added back into the CS, giving you the disk space back. We should also verify the output of the Fdisk command to ensure it creates the MBR correctly.

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Answer 14

Nov 12, 2017 10:44 AM in response to Loner T

That didn't seem to work.

The Core Storage Logical Volume UUID is A73082BE-C450-44D6-BE6D-92C37182E7AE

Started CoreStorage operation

Checking prerequisites for resizing Logical-Physical volume stack

Shrinking Logical-Physical volume stack

Verifying file system

Using live mode

Performing live verification

Checking Journaled HFS Plus volume

Checking extents overflow file

Checking catalog file

Checking multi-linked files

Checking catalog hierarchy

Checking extended attributes file

Checking volume bitmap

Checking volume information

The volume Macintosh HD appears to be OK

File system check exit code is 0

Shrinking file system

Error: -69787: The partition cannot be resized; try reducing the amount of change in the size of the partition

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Answer 15

Nov 12, 2017 10:59 AM in response to Loner T

I don't still have it. I removed it in BCA, like you said.

From diskutil list

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *121.3 GB
disk0

1: EFI EFI 209.7 MB
disk0s1

2: Apple_CoreStorage Macintosh HD 121.0 GB
disk0s2

3: Apple_Boot Boot OS X 134.2 MB
disk0s3

/dev/disk1 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *3.0 TB disk1

1: EFI EFI 209.7 MB
disk1s1

2: Apple_CoreStorage Macintosh HD 3.0 TB disk1s2

3: Apple_Boot Recovery HD 650.0 MB
disk1s4

/dev/disk2 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD +3.1 TB disk2

Logical Volume on disk0s2, disk1s2

A73082BE-C450-44D6-BE6D-92C37182E7AE

Unencrypted Fusion Drive

/dev/disk3 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: FDisk_partition_scheme *32.0 GB disk3

1: DOS_FAT_32 WININSTALL 32.0 GB disk3s1

Disk3 is just the flash drive that I'm using as an install disk, so this might show up in the list sometimes and sometimes it might not (when I remove it from the computer).

From diskutil cs list

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group AF994E04-C4E9-4B5E-AA2F-358D14EE484A

=========================================================

Name: Macintosh HD

Status: Online

Size: 3120722075648 B (3.1 TB)

Free Space:
245760 B (245.8 KB)

|

+-< Physical Volume 2A17E9A7-66D9-4813-AC93-055254F1C190

|
----------------------------------------------------

|
Index: 0

|
Disk: disk0s2

|
Status:
Online

|
Size: 120988852224 B (121.0 GB)

|

+-< Physical Volume 015DDA11-E6C3-411A-A094-8F59D7B75797

|
----------------------------------------------------

|
Index: 1

|
Disk: disk1s2

|
Status:
Online

|
Size: 2999733223424 B (3.0 TB)

|

+-> Logical Volume Family 1D90F443-DCF7-41E9-8FA3-81E8542FA48F

----------------------------------------------------------

Encryption Type: None

|

+-> Logical Volume A73082BE-C450-44D6-BE6D-92C37182E7AE

---------------------------------------------------

Disk: disk2

Status: Online

Size (Total): 3106191441920 B (3.1 TB)

Revertible: No

LV Name: Macintosh HD

Volume Name: Macintosh HD

Content Hint: Apple_HFS

LVG Type: Fusion, Sparse

Reply