iMac with Fusion Drive circle slash on boot

[timeshifter]

Approximately 3 year old 27" iMac. Circle slash on boot, which indicates problem with OS, etc.

Plan was to reinstall OS.

First tested by running built in diagnostics, no problems reported.

Second attempted Safe Mode boot, but it failed to circle slash.

Next I booted from High Sierra installer. Only volume showing during install was my external installer drive. Ran Disk Utility (GUI) and no internal drives appear.

Booted Sierra installer (not High Sierra). Same thing, except Disk Utility shows two internal drives. One 128GB SSD and one 4TB spinning disk. The SSD showed full, spinning disk empty.

Booted Internet Recovery which loaded an El Capitan installer. Again, can't see a volume to install to. Disk Utility from Terminal "diskutil list" shows what appears to mean that the Fusion Drive is broken.

At this point I'm planning to recreate the Fusion Drive and reinstall OS
https://support.apple.com/en-us/HT207584

Customer has a good Time Machine backup.

Is this a reasonable plan? Have I missed anything? Any other tips or tricks?

 

[Markverhyden]

That symbol typically indicates an macOS version that is not compatible/supported for the target hardware. Have you checked the serial number mfg date?

 

[timeshifter]

It’s a Fall 2015 model iMac.

 

[Markverhyden]

Then it sounds like the pairing was broken somehow. Had one of the drives been replaced or did this happen suddenly so to speak. Either way that's the only way to build a Fusion drive. This is a classic example why it's so important to have a bootable macOS drive with a live filesystem. Lets you boot from that and then operate on the patient.

 

[timeshifter]

Nothing changed, it happened all of the sudden. They had been out town, may have had power issues. But the system was working when they returned and they were using it. Not sure if they restarted the machine or whatever.

So a bootable macOS? I’ve never really done this. I do have multiple Mac OS bootable installers on my iODD. I know they were popular especially when all Macs had FireWire. So just install to an external USB drive?

I guess you can boot modern Macs from USB. But the thought of running an OS from USB makes me shudder.

 

[Markverhyden]

Well, I can assure you I don't run around using that as a daily driver. LOL!!! But it works well enough for basic trouble shooting, diags, etc. I had a firewire drive but also sprung for a Thunderbolt a few years ago. Much more responsive and you can use it for regular macOS file transfers, etc. Most of them come with USB 3 which is pretty fast. You can get a USB 3 stick at a reasonable price as well.

 

[timeshifter]

But it works well enough for basic trouble shooting, diags, etc.

What tools do you load on yours?

 

[lcoughey]

Pull the hard drive and test it. Most of these systems came with a Seagate dm series drive that has a lot of failures.

 

[timeshifter]

Pull the hard drive and test it. Most of these systems came with a Seagate dm series drive that has a lot of failures.

That sounds like a good idea. I'm trying to think of ways to test the drive without pulling it. This is a big iMac where the screen is glued onto the frame. Would really like to avoid opening it up unless absolutely necessary.

 

[Markverhyden]

You can boot from partedmagic and run their tests. On software. For a USB stick I just use basic OS X and if I want something specific I'll download it. On the TB drive it's identical to my daily driver except no email. This thread discusses what various people use. Pretty old so I'll see if I have any thing new I've been using.

 

[timeshifter]

You can boot from partedmagic and run their tests.

You can

The copy I'm using that works on nearly every PC I've tried it on in the past, won't boot on this iMac. It gets to a point then the screen goes black and hangs. I even tried their "black screen fix" boot selection, but that took me to a text mode and didn't have the tests I needed. I'm going to download the latest version and try again.

Here's what I found when booting a live macOS disk and running a tool called smartctl

Techs-MBP:~ techboot$ diskutil list

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: *4.1 GB disk0


/dev/disk1 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *121.3 GB disk1

1: EFI EFI 209.7 MB disk1s1

2: Apple_CoreStorage Macintosh HD 121.0 GB disk1s2

3: Apple_Boot Boot OS X 134.2 MB disk1s3


/dev/disk2 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *128.0 GB disk2

1: EFI EFI 209.7 MB disk2s1

2: Apple_HFS GoldSSD 127.2 GB disk2s2

3: Apple_Boot Recovery HD 650.0 MB disk2s3




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


Techs-MBP:sbin techboot$ sudo /usr/local/sbin/smartctl -a /dev/disk0

smartctl 6.6 2017-11-05 r4594 [Darwin 17.7.0 x86_64] (sf-6.6-1)

Copyright (C) 2002-17, Bruce Allen, Christian Franke, www.smartmontools.org


=== START OF INFORMATION SECTION ===

Device Model: ST3000DM001

Serial Number: ZA502P59

LU WWN Device Id: 5 000c50 0871c3e46

Firmware Version: AQ03

User Capacity: 137,438,952,960 bytes [137 GB]

Sector Size: 512 bytes logical/physical

Rotation Rate: 7200 rpm

Device is: Not in smartctl database [for details use: -P showall]

ATA Version is: ATA8-ACS T13/1699-D revision 4

SATA Version is: SATA 3.0, 6.0 Gb/s

Local Time is: Mon Sep 24 08:27:10 2018 EDT

SMART support is: Available - device has SMART capability.

SMART support is: Enabled


Read SMART Data failed: Undefined error: 0


=== START OF READ SMART DATA SECTION ===

SMART Status command failed: Undefined error: 0

SMART overall-health self-assessment test result: UNKNOWN!

SMART Status, Attributes and Thresholds cannot be read.


Read SMART Log Directory failed: Undefined error: 0


Read SMART Error Log failed: Undefined error: 0


Read SMART Self-test Log failed: Undefined error: 0


Selective Self-tests/Logging not supported



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


Techs-MBP:sbin techboot$ sudo /usr/local/sbin/smartctl -a /dev/disk1

smartctl 6.6 2017-11-05 r4594 [Darwin 17.7.0 x86_64] (sf-6.6-1)

Copyright (C) 2002-17, Bruce Allen, Christian Franke, www.smartmontools.org


=== START OF INFORMATION SECTION ===

Model Family: Apple SD/SM/TS...E/F/G SSDs

Device Model: APPLE SSD SM0128G

Serial Number: S2PBNYAG969431

LU WWN Device Id: 5 002538 900000000

Firmware Version: BXW5TA0Q

User Capacity: 121,332,826,112 bytes [121 GB]

Sector Sizes: 512 bytes logical, 4096 bytes physical

Rotation Rate: Solid State Device

Device is: In smartctl database [for details use: -P show]

ATA Version is: ATA8-ACS T13/1699-D revision 4c

SATA Version is: SATA 3.0, 6.0 Gb/s (current: 6.0 Gb/s)

Local Time is: Mon Sep 24 08:28:41 2018 EDT

SMART support is: Available - device has SMART capability.

SMART support is: Enabled


=== START OF READ SMART DATA SECTION ===

SMART overall-health self-assessment test result: PASSED


General SMART Values:

Offline data collection status: (0x00) Offline data collection activity

was never started.

Auto Offline Data Collection: Disabled.

Self-test execution status: ( 0) The previous self-test routine completed

without error or no self-test has ever

been run.

Total time to complete Offline

data collection: ( 0) seconds.

Offline data collection

capabilities: (0x53) SMART execute Offline immediate.

Auto Offline data collection on/off support.

Suspend Offline collection upon new

command.

No Offline surface scan supported.

Self-test supported.

No Conveyance Self-test supported.

Selective Self-test supported.

SMART capabilities: (0x0003) Saves SMART data before entering

power-saving mode.

Supports SMART auto save timer.

Error logging capability: (0x01) Error logging supported.

General Purpose Logging supported.

Short self-test routine

recommended polling time: ( 2) minutes.

Extended self-test routine

recommended polling time: ( 10) minutes.


SMART Attributes Data Structure revision number: 1

Vendor Specific SMART Attributes with Thresholds:

ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE

1 Raw_Read_Error_Rate 0x001a 200 200 000 Old_age Always - 0

5 Reallocated_Sector_Ct 0x0033 100 100 000 Pre-fail Always - 0

9 Power_On_Hours 0x0032 095 095 000 Old_age Always - 25236

12 Power_Cycle_Count 0x0032 099 099 000 Old_age Always - 153

169 Unknown_Apple_Attrib 0x0013 247 247 010 Pre-fail Always - 837562663392

173 Wear_Leveling_Count 0x0032 191 191 100 Old_age Always - 369386258600

174 Host_Reads_MiB 0x0022 099 099 000 Old_age Always - 7203307

175 Host_Writes_MiB 0x0022 099 099 000 Old_age Always - 5875067

192 Power-Off_Retract_Count 0x0012 099 099 000 Old_age Always - 59

194 Temperature_Celsius 0x0022 072 036 000 Old_age Always - 28 (Min/Max 18/64)

197 Current_Pending_Sector 0x0022 100 100 000 Old_age Always - 0

199 UDMA_CRC_Error_Count 0x001a 200 199 000 Old_age Always - 0


SMART Error Log Version: 1

No Errors Logged


SMART Self-test log structure revision number 1

No self-tests have been logged. [To run self-tests, use: smartctl -t]


Warning! SMART Selective Self-Test Log Structure error: invalid SMART checksum.

SMART Selective self-test log data structure revision number 1

SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS

1 0 0 Not_testing

2 0 0 Not_testing

3 0 0 Not_testing

4 0 0 Not_testing

5 0 0 Not_testing

255 0 65535 Read_scanning was never started

Selective self-test flags (0x0):

After scanning selected spans, do NOT read-scan remainder of disk.

If Selective self-test is pending on power-up, resume after 0 minute delay.

 

[timeshifter]

Can boot Parted Magic now, just bought the 08-2018 version for $11. Previous was 03-2017 that had trouble.

Anyway, weird way that the spinning disk is reported with their tool. Shows the spinning disk, but capacity is shown as 137GB. As I type this I seem to recall that's a size that might be reported when OS / hardware has some limitation with a large drive. Anyway, here's what I see:

 

[timeshifter]

More signs pointing to spinning drive failure. Tried to recreate the Fusion Drive per the instructions at Apple I linked in the OP. Got an error stating "69760 unable to write to the last block of the device". Next I tried to manually setup each drive as an individual drive. Was able to erase the SSD and create a new Mac volume, went fine. But could not do the same for the spinning disk. Tried booted from a regular OS and from Recovery. Both times Disk Utility threw this error:

 

[Markverhyden]

You can

The copy I'm using that works on nearly every PC I've tried it on in the past, won't boot on this iMac. It gets to a point then the screen goes black and hangs. I even tried their "black screen fix" boot selection, but that took me to a text mode and didn't have the tests I needed. I'm going to download the latest version and try again.

Here's what I found when booting a live macOS disk and running a tool called smartctl

Techs-MBP:~ techboot$ diskutil list

/dev/disk0 (internal, physical):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:                                                   *4.1 GB     disk0


/dev/disk1 (internal, physical):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *121.3 GB   disk1

   1:                        EFI EFI                     209.7 MB   disk1s1

   2:          Apple_CoreStorage Macintosh HD            121.0 GB   disk1s2

   3:                 Apple_Boot Boot OS X               134.2 MB   disk1s3


/dev/disk2 (external, physical):

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *128.0 GB   disk2

   1:                        EFI EFI                     209.7 MB   disk2s1

   2:                  Apple_HFS GoldSSD                 127.2 GB   disk2s2

   3:                 Apple_Boot Recovery HD             650.0 MB   disk2s3




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


Techs-MBP:sbin techboot$ sudo /usr/local/sbin/smartctl -a /dev/disk0

smartctl 6.6 2017-11-05 r4594 [Darwin 17.7.0 x86_64] (sf-6.6-1)

Copyright (C) 2002-17, Bruce Allen, Christian Franke, www.smartmontools.org


=== START OF INFORMATION SECTION ===

Device Model:     ST3000DM001

Serial Number:    ZA502P59

LU WWN Device Id: 5 000c50 0871c3e46

Firmware Version: AQ03

User Capacity:    137,438,952,960 bytes [137 GB]

Sector Size:      512 bytes logical/physical

Rotation Rate:    7200 rpm

Device is:        Not in smartctl database [for details use: -P showall]

ATA Version is:   ATA8-ACS T13/1699-D revision 4

SATA Version is:  SATA 3.0, 6.0 Gb/s

Local Time is:    Mon Sep 24 08:27:10 2018 EDT

SMART support is: Available - device has SMART capability.

SMART support is: Enabled


Read SMART Data failed: Undefined error: 0


=== START OF READ SMART DATA SECTION ===

SMART Status command failed: Undefined error: 0

SMART overall-health self-assessment test result: UNKNOWN!

SMART Status, Attributes and Thresholds cannot be read.


Read SMART Log Directory failed: Undefined error: 0


Read SMART Error Log failed: Undefined error: 0


Read SMART Self-test Log failed: Undefined error: 0


Selective Self-tests/Logging not supported



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


Techs-MBP:sbin techboot$ sudo /usr/local/sbin/smartctl -a /dev/disk1

smartctl 6.6 2017-11-05 r4594 [Darwin 17.7.0 x86_64] (sf-6.6-1)

Copyright (C) 2002-17, Bruce Allen, Christian Franke, www.smartmontools.org


=== START OF INFORMATION SECTION ===

Model Family:     Apple SD/SM/TS...E/F/G SSDs

Device Model:     APPLE SSD SM0128G

Serial Number:    S2PBNYAG969431

LU WWN Device Id: 5 002538 900000000

Firmware Version: BXW5TA0Q

User Capacity:    121,332,826,112 bytes [121 GB]

Sector Sizes:     512 bytes logical, 4096 bytes physical

Rotation Rate:    Solid State Device

Device is:        In smartctl database [for details use: -P show]

ATA Version is:   ATA8-ACS T13/1699-D revision 4c

SATA Version is:  SATA 3.0, 6.0 Gb/s (current: 6.0 Gb/s)

Local Time is:    Mon Sep 24 08:28:41 2018 EDT

SMART support is: Available - device has SMART capability.

SMART support is: Enabled


=== START OF READ SMART DATA SECTION ===

SMART overall-health self-assessment test result: PASSED


General SMART Values:

Offline data collection status:  (0x00) Offline data collection activity

was never started.

Auto Offline Data Collection: Disabled.

Self-test execution status:      (   0) The previous self-test routine completed

without error or no self-test has ever

been run.

Total time to complete Offline

data collection: (    0) seconds.

Offline data collection

capabilities:  (0x53) SMART execute Offline immediate.

Auto Offline data collection on/off support.

Suspend Offline collection upon new

command.

No Offline surface scan supported.

Self-test supported.

No Conveyance Self-test supported.

Selective Self-test supported.

SMART capabilities:            (0x0003) Saves SMART data before entering

power-saving mode.

Supports SMART auto save timer.

Error logging capability:        (0x01) Error logging supported.

General Purpose Logging supported.

Short self-test routine

recommended polling time:  (   2) minutes.

Extended self-test routine

recommended polling time:  (  10) minutes.


SMART Attributes Data Structure revision number: 1

Vendor Specific SMART Attributes with Thresholds:

ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE

  1 Raw_Read_Error_Rate     0x001a   200   200   000    Old_age   Always       -       0

  5 Reallocated_Sector_Ct   0x0033   100   100   000    Pre-fail  Always       -       0

  9 Power_On_Hours          0x0032   095   095   000    Old_age   Always       -       25236

 12 Power_Cycle_Count       0x0032   099   099   000    Old_age   Always       -       153

169 Unknown_Apple_Attrib    0x0013   247   247   010    Pre-fail  Always       -       837562663392

173 Wear_Leveling_Count     0x0032   191   191   100    Old_age   Always       -       369386258600

174 Host_Reads_MiB          0x0022   099   099   000    Old_age   Always       -       7203307

175 Host_Writes_MiB         0x0022   099   099   000    Old_age   Always       -       5875067

192 Power-Off_Retract_Count 0x0012   099   099   000    Old_age   Always       -       59

194 Temperature_Celsius     0x0022   072   036   000    Old_age   Always       -       28 (Min/Max 18/64)

197 Current_Pending_Sector  0x0022   100   100   000    Old_age   Always       -       0

199 UDMA_CRC_Error_Count    0x001a   200   199   000    Old_age   Always       -       0


SMART Error Log Version: 1

No Errors Logged


SMART Self-test log structure revision number 1

No self-tests have been logged.  [To run self-tests, use: smartctl -t]


Warning! SMART Selective Self-Test Log Structure error: invalid SMART checksum.

SMART Selective self-test log data structure revision number 1

 SPAN  MIN_LBA  MAX_LBA  CURRENT_TEST_STATUS

    1        0        0  Not_testing

    2        0        0  Not_testing

    3        0        0  Not_testing

    4        0        0  Not_testing

    5        0        0  Not_testing

  255        0    65535  Read_scanning was never started

Selective self-test flags (0x0):

  After scanning selected spans, do NOT read-scan remainder of disk.

If Selective self-test is pending on power-up, resume after 0 minute delay.

It's obvious /dev/disk0 is an issue

Device Model: ST3000DM001 = 3tb drive

Serial Number: ZA502P59

LU WWN Device Id: 5 000c50 0871c3e46

Firmware Version: AQ03

User Capacity: 137,438,952,960 bytes [137 GB] = not even close

 

[Porthos]

Device Model: ST3000DM001
I cringe and expect to have to replace all Segate DM series drives.

 

[labtech]

Very common for the 3TB Seagate model to fail on those.

 

[Markverhyden]

Device Model: ST3000DM001
I cringe and expect to have to replace all Segate DM series drives.

Very common for the 3TB Seagate model to fail on those.

Apple only chooses the finest..... LOL!!!!

 

[labtech]

Apple only chooses the finest..... LOL!!!!

They get cheaper and cheaper by the year.

 

[lcoughey]

There was a recall for them by Apple - https://www.macrumors.com/2015/06/19/apple-27-imac-3tb-hdd-replacement-program/

By a small number, they mean, "All of them"

 

[timeshifter]

There was a recall for them by Apple - https://www.macrumors.com/2015/06/19/apple-27-imac-3tb-hdd-replacement-program/

By a small number, they mean, "All of them"

My customer's computer is a Late 2015 model. The Mac Rumors article states the recall is for "late 2012 27-inch iMacs sold between December 2012 and September 2013 may fail under certain conditions". Apple replaced the 1TB drive on my 2009 27-inch iMac under a similar program.

I did talk to Apple support and was told there was no recall for this system. I'll be at the Apple Store today for a different matter and will double-check and see what they'll charge to replace if not. Maybe I could point out the high number of failures of this series of drives?