iMac 27" 5K + Pegasus2 R6, drops LD0 on boot

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Level 1

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iMac 27" 5K + Pegasus2 R6, drops LD0 on boot

Hi

I have just gotten this brand new iMac with 1TB SSD disk. added Pegasus2 R6 (total 24TB) connected with a corning fibercable. Created 3 logical disks. LD0 is for data, LD1 is for backups and LD2 is for timemachine. This worked fine... but... now it happens that after boot the icon for LD0 is not showing up on the desktop, or in finder! Using Disk Utility, the volume IS mounted and visible, and when I ask Disk Utility to test, the icon will briefly be visible, and then go away!!!

Without a large statistic material it seems that on booting from cold (no mains at the iMac during the night) this vil happen. choosing "start again" from the apple icon will not help. but shutting down, waiting a bit and then pressing the power button on the iMac, only then LD0 will reappear. WHY??????? It may also happen after prolonged sleep state.

the data is alive on the drive but files cannot be opened as they appear to be read only.

I have talked to Promise, and they suggest its something in OS X

Is this a bug or a feature???

I run Sierra 10.12.5.

kind regards

Palle Jensen

iMac (Retina 5K, 27-inch, 2017), macOS Sierra (10.12.5), 1TB SSD

Posted on Jul 5, 2017 9:40 AM

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Answer 1

John Galt

Level 10

156,728 points

Jul 5, 2017 10:02 AM in response to GreyT

From what you describe, you may have formatted the external drive incorrectly.

Format it according to the "Formatting a backup disk for use with Time Machine" instructions in the following: Backup disks you can use with Time Machine - Apple Support.

... connected with a corning fibercable.

I don't know what that is. The Pegasus2 uses Thunderbolt. Unless it is connected to your iMac using a Thunderbolt cable, it won't work.

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Answer 2

Eric Root

Level 10

685,311 points

Jul 5, 2017 10:12 AM in response to GreyT

Have you run Disk Utility/First Aid on the drive? Do a Get Info (command - I) on the drive and see if there is an Ignore ownership option. Also see what the permissions are set to.

(no mains at the iMac during the night)

What do you mean by the above?

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Answer 3

GreyT Author

Level 1

10 points

Jul 5, 2017 10:18 AM in response to Eric Root

command I have a checkmark at the bottom for ignore ownership, but so has the LD1, which is stable and available!

I just wonder if it is because LD0 is the first drive it is not always recognized.

All 3 drives have me accepted as read and write.

by no mains I mean iMac printer scanner and lamp is connected to same outlet, which I turn of at night. when I first set up the iMac and pegasus it was connected to an always on outlet, and as I remember the problem was not there.

Palle

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Answer 4

GreyT Author

Level 1

10 points

Jul 5, 2017 10:22 AM in response to John Galt

thank you for your suggestion, but there is no problem with the timemachine disk only with the 'data disk' and they are formatted in the same way. I guess that since the data disk is useful most of the times it could not have format errors

the corning thunderbolt cable is a unit you use when the disk is placed at a distance longer than 'copper' thunderbolt cables. my cable is 100 feet, mostly on a roll.

Palle

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