External Drive won't mount, shows in disk utility

[wwohl]

Need some help MacRumors community. My 2012 Mac mini uses two 3TB drives in a single 2 Bay external enclosure for media. Two WD RED NAS drives inside a Mediasonic 2 bay RAID enclosure (set to normal aka individual disks). Both drives are formatted as OS X extended journaled

I just set this up about a month ago and its been working fine. Suddenly the drives stopped mounting to the desktop and finder. Ive replaced the USB 3 cable and even see the drive activity lights flicker when I first plug it in.

If I open disk utility, they show up. Running First Aid did nothing. Clicking on the drive to show more info shows its status as "not mounted"

Any help?

 

[BLUEDOG314]

try running diskutil list in terminal and get the identifiers, like disk1s1 or something like that, then doing diskutil mount disk1s1. otherwise what happens when you hit mount in disk utility?

 

[wwohl]

try running diskutil list in terminal and get the identifiers, like disk1s1 or something like that, then doing diskutil mount disk1s1. otherwise what happens when you hit mount in disk utility?

Its able to mount the 300mb partition thats labeled EFI. Wont mount the s2 main portion of the drive

 

[wwohl]

Last login: Thu Mar 3 17:17:36 on ttys000

Williams-Mini:~ wwohl$ diskutil list

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *250.1 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_HFS OSX SSD 249.2 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

/dev/disk1 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk1

1: EFI EFI 209.7 MB disk1s1

2: Apple_HFS Install OS X El Capitan 999.9 GB disk1s2

/dev/disk2 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *3.0 TB disk2

1: EFI EFI 209.7 MB disk2s1

2: Apple_HFS 3.0 TB disk2s2

/dev/disk3 (external, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *3.0 TB disk3

1: EFI EFI 209.7 MB disk3s1

2: Apple_HFS 3.0 TB disk3s2

Williams-Mini:~ wwohl$ diskutil mount disk2s1

Volume EFI on disk2s1 mounted

Williams-Mini:~ wwohl$ diskutil mount disk2s2

Volume on disk2s2 failed to mount

If the volume is damaged, try the "readOnly" option

Williams-Mini:~ wwohl$ diskutil mount readonly disk2s2

Volume on disk2s2 failed to mount

If the volume is damaged, try the "readOnly" option

Williams-Mini:~ wwohl$ diskutil verifydisk disk2

Started partition map verification on disk2

Checking prerequisites

Checking the partition list

Checking the partition map size

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 Core Storage Physical Volume partitions

The partition map appears to be OK

Finished partition map verification on disk2

Williams-Mini:~ wwohl$ diskutil repairdisk disk2

Repairing the partition map might erase disk2s1, proceed? (y/N) y

Started partition map repair on disk2

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

Reviewing boot support loaders

Checking Core Storage Physical Volume partitions

Updating Windows boot.ini files as required

The partition map appears to be OK

Finished partition map repair on disk2

Williams-Mini:~ wwohl$ diskutil info disk2

Device Identifier: disk2

Device Node: /dev/disk2

Whole: Yes

Part of Whole: disk2

Device / Media Name: EFRX-68EUZN0



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: USB

SMART Status: Not Supported



Total Size: 3.0 TB (3000592982016 Bytes) (exactly 5860533168 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)



Device Location: External

Removable Media: No



Virtual: No

OS 9 Drivers: No

Low Level Format: Not supported



Williams-Mini:~ wwohl$

 

[Fishrrman]

OP:

If you're still having problems, I'd suggest this:

- Get ANOTHER enlcosure, or USB3/SATA docking station, or a USB3/SATA "dongle adapter".

- Connect the drives to it, one at a time.

- Can you see them this way? Can you mount them? Can you access them?

 

[wwohl]

OP:

If you're still having problems, I'd suggest this:

- Get ANOTHER enlcosure, or USB3/SATA docking station, or a USB3/SATA "dongle adapter".

- Connect the drives to it, one at a time.

- Can you see them this way? Can you mount them? Can you access them?

I did try a USB3 to SATA adapter I had and continued to experience the same issues.
I either got a bug in there that destroyed the file directories or the enclosure some how messed up the data. After lots of research, decided to wipe and reformat the drives. Fortunately I had a third backup drive that was only a few weeks out of date.

 

[DeltaMac]

Have you tried asking at the MediaSonic customer forum?
http://forum.mediasonic.ca
That site appears to be fairly responsive to customers (just what I see, but no actual experience)

 

[wwohl]

Just a little update on this issues. Its been nearly three months since this originally occurred and a few nights ago it finally happened again. This time, while I was writing to one of the drives. The transfer hung up, the drives disconnected and never remounted. All of the data is once again unreadable.
Ill be reaching out to media sonic customer service and on the forums. I have other external drives running on this computer and some of them are mirror copies of what was on the failed enclosure. Ive never experienced a failure like this and now twice (on both drives) in this enclosure. Im going to assume its the enclosure.

I bit the bullet and bought an OWC thunder bay to replace the current setup. Ill let you all know what I hear from MediaSonic