Can't create Windows partition on roll-your-own Fusion drive

Question

Level 1

104 points

Can't create Windows partition on roll-your-own Fusion drive

I've created my own Fusion drive from an internal SATA HDD and an SSD in the optical drive PATA port on a 2008 iMac. I now want to use Boot Camp. Boot Camp won't create a partition on my Fusion drive because, apparently, it thinks I'm using an external drive. When I use Disk Utility to partition the drive, it creates a 300GB partition when I've asked for a 47GB partition, leaving me almost no free space on my main partition.

What's going on here? Why is Disk Utility misbehaving? Is there a way to make Disk Utility create a ~40GB partition on my Fusion drive? Perhaps by creating it as an HFS+ partition, then reformatting it, or using the command line version of Disk Utility? I'm reticent to experiment as this is my main machine, and I've heard horror stories about hosing drives in this manner.

iMac, OS X Yosemite (10.10)

Posted on Feb 16, 2015 9:31 AM

Reply

Answer 1

Loner T

Level 9

59,513 points

Feb 16, 2015 9:53 AM in response to Zarquon42

Disk Utility is broken when dealing with Fusion drives. You will need to use diskutil cs commands.

Can you post the output of the following commands?

diskutil list

diskutil cs list

sudo gpt -vv -r show /dev/disk0

sudo gpt -vv -r show /dev/disk1

Reply

Answer 2

Zarquon42 Author

Level 1

104 points

Feb 16, 2015 10:29 AM in response to Loner T

Jane:~ jim$ 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 255.7 GB disk0s2

3: Apple_Boot Boot OS X 134.2 MB disk0s3

/dev/disk1

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *640.1 GB disk1

1: EFI EFI 209.7 MB disk1s1

2: Apple_CoreStorage 627.1 GB disk1s2

3: Apple_Boot Recovery HD 650.1 MB disk1s3

4: Apple_HFS eDrive 12.0 GB disk1s4

/dev/disk2

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Jane's Brain *882.2 GB disk2

Logical Volume on disk0s2, disk1s2

1E68BA1C-6FC8-4650-BFC8-F2F6D05C8B98

Unencrypted

/dev/disk3

#: TYPE NAME SIZE IDENTIFIER

0: FDisk_partition_scheme *500.1 GB disk3

1: Apple_HFS SylerNet Adjunct 269.1 GB disk3s1

2: DOS_FAT_32 ADJUNCT FAT 230.9 GB disk3s2

/dev/disk4

#: TYPE NAME SIZE IDENTIFIER

0: FDisk_partition_scheme *15.6 GB disk4

1: DOS_FAT_32 BOOT CAMP 15.6 GB disk4s1

/dev/disk5

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *320.1 GB disk5

1: EFI EFI 209.7 MB disk5s1

2: Apple_HFS Jane's Old Brain 319.7 GB disk5s2

Jane:~ jim$ diskutil cs list

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group A51253AD-E99C-4B47-95C0-5BF84CEC1DD3

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

Name: JaneFusionDrive

Status: Online

Size: 882861637632 B (882.9 GB)

Free Space: 6901760 B (6.9 MB)

|

+-< Physical Volume 4F085C3F-76AE-4998-9607-F63B55F44615

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

| Index: 0

| Disk: disk0s2

| Status: Online

| Size: 255716540416 B (255.7 GB)

|

+-< Physical Volume 4A8460C6-E2FD-4226-B136-BB1FA8185D1C

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

| Index: 1

| Disk: disk1s2

| Status: Online

| Size: 627145097216 B (627.1 GB)

|

+-> Logical Volume Family 1BA9B312-6CC6-4485-9188-A645D025A2CD

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

Encryption Status: Unlocked

Encryption Type: None

Conversion Status: NoConversion

Conversion Direction: -none-

Has Encrypted Extents: No

Fully Secure: No

Passphrase Required: No

|

+-> Logical Volume 1E68BA1C-6FC8-4650-BFC8-F2F6D05C8B98

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

Disk: disk2

Status: Online

Size (Total): 882217189376 B (882.2 GB)

Conversion Progress: -none-

Revertible: No

LV Name: Jane's Brain

Volume Name: Jane's Brain

Content Hint: Apple_HFS

Jane:~ jim$ sudo gpt -vv -r show /dev/disk0

gpt show: /dev/disk0: mediasize=256060514304; sectorsize=512; blocks=500118192

gpt show: /dev/disk0: PMBR at sector 0

gpt show: /dev/disk0: Pri GPT at sector 1

gpt show: /dev/disk0: Sec GPT at sector 500118191

start size index contents

0 1 PMBR

1 1 Pri GPT header

2 32 Pri GPT table

34 6

40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

409640 499446368 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

499856008 262144 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

500118152 7

500118159 32 Sec GPT table

500118191 1 Sec GPT header

Jane:~ jim$ sudo gpt -vv -r show /dev/disk1

gpt show: /dev/disk1: mediasize=640135028736; sectorsize=512; blocks=1250263728

gpt show: /dev/disk1: PMBR at sector 0

gpt show: /dev/disk1: Pri GPT at sector 1

gpt show: /dev/disk1: Sec GPT at sector 1250263727

start size index contents

0 1 PMBR

1 1 Pri GPT header

2 32 Pri GPT table

34 6

40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

409640 1224892768 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

1225302408 1269760 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

1226572168 23429256 4 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

1250001424 262271

1250263695 32 Sec GPT table

1250263727 1 Sec GPT header

Reply

Answer 3

Zarquon42 Author

Level 1

104 points

Feb 16, 2015 10:47 AM in response to Zarquon42

The "eDrive" is the TechTool partition, and of course I got rid of it before I tried to repartition with Disk Utility, otherwise it wouldn't have worked at all.

Reply

Answer 4

Loner T

Level 9

59,513 points

Feb 16, 2015 10:56 AM in response to Zarquon42

1. Assuming the SSD is the 256GB disk, do you want Windows on the SSD. You are limited by it's size.

2. If you want Windows on HDD, you will have to use diskutil cs ResizeStack and create space, which can be formatted as FAT. This also requires a custom Hybrid MBR and ensuring that the Windows installer is pointed to this FAT partition, and nothing else.

3. I would highly recommend a TM backup, before you make any changes.

Here is the man page of the undocumented resizeStack verb. Bootcamp Assistant uses this and DM callbacks to execute partitioning on Fusion drives.

diskutil cs resizestack

Usage: diskutil coreStorage resizeStack

lvUUID|MountPoint|DiskIdentifier|DeviceNode [pvUUID] size

[part1Format part1Name part1Size part2Format part2Name part2Size

part3Format part3Name part3Size ...]

Resize both a logical volume and one of its underlying physical volumes in a

single operation. A single physical volume is always chosen for the underlying

shrink or grow, even if the logical volume's logical volume group is backed by

more than one physical volume. If you do not specify a particular physical

volume, then one is chosen for you. Note that if this is a grow operation,

this verb is limited by the physical volume's partition's room to grow.

Specifying zero as the size asks for an "automatic" grow-to-fill operation.

If this is a shrink operation, you can optionally request that new partitions

be created in the newly-formed free space gap in the partition map.

Again, note that this only resizes one of the underlying physical volumes; if

you need more sophistication in managing your topology, you should use the

separate physical and logical volume resize verbs.

Example: diskutil coreStorage resizeStack

11111111-2222-3333-4444-555555555555 10g JHFS+ New 1g

Be aware that BC/Windows installation uses the Model Identifier of the iMac to set NVRAM parameters to boot from the non-existent Optical drive. Bootcamp dislikes hardware modifications. 😉

Reply

Answer 5

Zarquon42 Author

Level 1

104 points

Feb 16, 2015 11:16 AM in response to Loner T

Thanks. I'll refresh my backup, give it a try, then report the results.

Reply

Answer 6

Zarquon42 Author

Level 1

104 points

Feb 16, 2015 11:17 AM in response to Loner T

So do I first create the partition with Disk Utility, then resize it with this command?

Reply

Answer 7

Loner T

Level 9

59,513 points

Feb 16, 2015 11:20 AM in response to Zarquon42

No. This command will do the resize and create a partition in the space that is freed up using the resize operation.

Reply

Answer 8

Zarquon42 Author

Level 1

104 points

Feb 16, 2015 11:21 AM in response to Loner T

Can I leave my eDrive in place or should I remove it first?

Reply

Answer 9

Loner T

Level 9

59,513 points

Feb 16, 2015 11:33 AM in response to Zarquon42

Leave it as is. It will onto interfere with the resize operation. The disk will remain a GPT-only disk.

Reply

Answer 10

Zarquon42 Author

Level 1

104 points

Feb 16, 2015 2:42 PM in response to Loner T

I'm having some trouble figuring out how to format the command. I tried

diskutil cs resizeStack 1E68BA1C-6FC8-4650-BFC8-F2F6D05C8B98 0g MS-DOS BOOTCAMP 40g

but it returned

Error: -69743: The new size must be different than the existing size

Reply

Answer 11

Loner T

Level 9

59,513 points

Feb 16, 2015 3:19 PM in response to Zarquon42

The following command will shrink LV (Jane's Brain) by resizing the underlying physical disk (disk1s2) from 627g to 520g and create a 106g FAT32 volume called BOOTCAMP on that disk using the freed up disk space.

diskutil cs resizeStack 1E68BA1C-6FC8-4650-BFC8-F2F6D05C8B98 4A8460C6-E2FD-4226-B136-BB1FA8185D1C 520g fat32 BOOTCAMP 106g

Reply

Answer 12

Zarquon42 Author

Level 1

104 points

Feb 16, 2015 5:19 PM in response to Loner T

Well. I did

diskutil cs resizeStack 1E68BA1C-6FC8-4650-BFC8-F2F6D05C8B98 4A8460C6-E2FD-4226-B136-BB1FA8185D1C 587g fat32 BOOTCAMP 40g

and it worked…sort of. I indeed have a 40gb Windows partition…and 255gb of free space below it. Jane's Brain now has 21gb free.

Sigh.

Reply

Answer 13

Loner T

Level 9

59,513 points

Feb 16, 2015 6:00 PM in response to Zarquon42

Can post the output of sudo gpt -vv -r show /dev/disk1?

Reply

Answer 14

Zarquon42 Author

Level 1

104 points

Feb 16, 2015 6:02 PM in response to Loner T

gpt show: /dev/disk1: mediasize=640135028736; sectorsize=512; blocks=1250263728

gpt show: /dev/disk1: Suspicious MBR at sector 0

gpt show: /dev/disk1: Pri GPT at sector 1

gpt show: /dev/disk1: Sec GPT at sector 1250263727

start size index contents

0 1 MBR

1 1 Pri GPT header

2 32 Pri GPT table

34 6

40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

409640 648296544 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

648706184 1269760 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

649975944 1912

649977856 78123008 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

728100864 498471304

1226572168 23429256 5 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

1250001424 262271

1250263695 32 Sec GPT table

1250263727 1 Sec GPT header

Reply

Answer 15

Loner T

Level 9

59,513 points

Feb 16, 2015 6:08 PM in response to Zarquon42

What was done between

Jane:~ jim$ sudo gpt -vv -r show /dev/disk1

gpt show: /dev/disk1: mediasize=640135028736; sectorsize=512; blocks=1250263728

gpt show: /dev/disk1: PMBR at sector 0

gpt show: /dev/disk1: Pri GPT at sector 1

gpt show: /dev/disk1: Sec GPT at sector 1250263727

start size index contents

0 1 PMBR

1 1 Pri GPT header

2 32 Pri GPT table

34 6

40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

409640 1224892768 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

1225302408 1269760 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

1226572168 23429256 4 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

1250001424 262271

1250263695 32 Sec GPT table

1250263727 1 Sec GPT header

and

Zarquon42 wrote:

gpt show: /dev/disk1: mediasize=640135028736; sectorsize=512; blocks=1250263728

gpt show: /dev/disk1: Suspicious MBR at sector 0

gpt show: /dev/disk1: Pri GPT at sector 1

gpt show: /dev/disk1: Sec GPT at sector 1250263727

start size index contents

0 1 MBR

1 1 Pri GPT header

2 32 Pri GPT table

34 6

40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

409640 648296544 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

648706184 1269760 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

649975944 1912

649977856 78123008 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

728100864 498471304

1226572168 23429256 5 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

1250001424 262271

1250263695 32 Sec GPT table

1250263727 1 Sec GPT header

Did the first resizeStack fail partially? Do you have a screen shot of the output from the first attempt?

Reply