OS X - Disk not recognised - Help

[antpix]

Hi there,

Bit of a serious issue - been using IcyBox Hard Disk caddy to make two back up copies of image files.  The Caddy has stopped working and appears to have done something with my Mac. I tried an old IcyBox caddy, 'Disc is Unrecognised do you want to Initialise' It does allow Disc Utility to see the disc but not to mount it to Verify Disc or Repair permissions. I've tried different ports and cables, starting and restarting.

I've bought as replacements a Newer Tech caddy from OWC and also a Thunderbay 4 Thunderbolt array, expecting to be able to just plug in the disks and carry on. Unfortunately the discs come up with Unrecognised, DU will again see the discs but not do anything.

The file structure comes up as 0xEE which appears to be a Unix thing and most of the info about it is to do with dual booting into Bootcamp.

I've tried Diskwarrior in both caddies and the Thunderbay and the discs won't come up as options to work on ;-(

Digging deeper I've tried the info in this page https://nbalkota.wordpress.com/2013/01/13/recovering-a-non-readable-disk-on-mac-os-x/

Which brings back this report

localhost:~ anthonyupton$ diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *500.3 GB   disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            499.4 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:                            DW                     *67.6 MB    disk1
/dev/disk2
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     FDisk_partition_scheme                        *3.0 TB     disk2
   1:                       0xEE                         375.1 GB   disk2s1
localhost:~ anthonyupton$ sudo gpt recover /dev/disk2
Password:
gpt recover: /dev/disk2: no primary or secondary GPT headers, can't recover
localhost:~ anthonyupton$ diskutil repairDisk /dev/disk2
Unable to repair this whole disk: A GUID Partition Table (GPT) partitioning scheme is required (-69773)
localhost:~ anthonyupton$

I've looked at http://www.cgsecurity.org/wiki/TestDisk as well, it recognised that something is wrong but the options on how to repair just confused the bejesus out of me and I'm loath to go much further for fear of really messing things up.

If anybody knows of a way to force Discwarrior to see the drive or can talk me through TestDisk I'd be most grateful, I'm really loath to format the discs  as it appears to be affecting all the back up discs around 15 TB worth of work!

Funnily enough it doesn't appear to be affecting a Lacie USB Tough Disc but a Seagate one is also un recognised.

[tonycollinet]

Not going to be able to help with the detail - but first port of call would be to try the disks (with new caddy) in a different computer - preferably different OS.

[Jaded]

Not much help, but rebooting, waiting, plugging in after restart, or any combination of these in any order has got a disk visible to DU or DW before.

Apparently if you do get DW to rebuild the directory don't automatically replace it, you get the disks mounted for comparison then copy the files off the old one

or something like that...

Found this on a google...

https://github.com/aburgh/Disk-Arbitrator

[antpix]

Thanks, tried all the normal alternatives of cables and machines and ports, 2 macs, restarts etc.

I've not tried a different OS, I've only got access to Windows machine and I'm pretty certain that they won't read a Mac disk.

I don't know enough about Terminal to go rooting around in there, so I'm steering clear, hence the request for help with TestDisk, which is a command line Utility. It knows something is wrong, but offers too many options as to the solution, all with pretty serious consequences, if I choose the wrong one.

I'm normally pretty good with Mac OS and can solve most problems, but Command Line gives me the shivers - I just don't see Code in the same way as others ;-)

Interesting info about the Auto replace on DW, I'll bear it in mind.

Any other ideas. Thanks

Ant

[Jaded]

Try DiskArbitrator, I've just got it to mount the Recovery partition on my MBP.

[antpix]

OK, so I braved TestDisk which has allowed me to see the files which I'm copying off now as Disk Utility says the disk is not Verifiable. But at least I can get the files and folder structure off

After copying will get Disk Warrior to look at it and see what it can do, and then Disk Utility.

TestDisk really is good, I just wish the documentation was better written.

Thanks for all the suggestions

[antpix]

So, TestDisk told me the Directory was 'inefficient' and offered to rebuild it, which seemed logical because of all the shenanigans before. So I let it do it's thing - the strange thing is whilst the data was all there, it now reported that my 3TB HD was a 2.2TB HD! Disk Utility reported the HD as being fine now, however I wasn't happy at loosing a shed load of storage space and I'm sure things would not be good for the future.

So I copied everything of, Repartioned the disk as this apparently goes deeper than just Erasing the data, which had been recommended and wrote the whole disk back to zeros, with one pass, so hopefully any nasty legacy data will have been overwritten and I can go one using the disks as normal.

A bit of a palaver, for both my back up disks to get corrupted at the same time, I'm obviously going to have to look at a more robust system! With data being written to at least two different hardware systems, as I believe it was the hardware failure which caused the Partition Tables to get corrupted in the first place.