
A client has an eSATA dock for SATA disks and he's been using a 2TB disk on his Mac. He says that he just came in one morning to see that it was claiming to be empty. When I ran the print command from parted I got the following: (parted) print Warning: /dev/sdd contains GPT signatures, indicating that it has a GPT table. However, it does not have a valid fake msdos partition table, as it should. Perhaps it was corrupted -- possibly by a program that doesn't understand GPT partition tables. Or perhaps you deleted the GPT table, and are now using an msdos partition table. Is this a GPT partition table? Yes/No? y Model: ATA eSATA-2 (scsi) Disk /dev/sdd: 2000GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 20.5kB 210MB 210MB fat32 EFI System Partition boot 2 210MB 2000GB 2000GB hfs+ Untitled A web search for what to do suggested creating a new label and using the rescue command: (parted) mklabel New disk label type? gpt Warning: The existing disk label on /dev/sdd will be destroyed and all data on this disk will be lost. Do you want to continue? Yes/No? y Warning: /dev/sdd contains GPT signatures, indicating that it has a GPT table. However, it does not have a valid fake msdos partition table, as it should. Perhaps it was corrupted -- possibly by a program that doesn't understand GPT partition tables. Or perhaps you deleted the GPT table, and are now using an msdos partition table. Is this a GPT partition table? Yes/No? y (parted) print Model: ATA eSATA-2 (scsi) Disk /dev/sdd: 2000GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags (parted) rescue Start? 1 End? 2000G Information: A fat32 primary partition was found at 20.5kB -> 210MB. Do you want to add it to the partition table? Yes/No/Cancel? yes (parted) print Model: ATA eSATA-2 (scsi) Disk /dev/sdd: 2000GB Sector size (logical/physical): 512B/512B Partition Table: gpt Number Start End Size File system Name Flags 1 20.5kB 210MB 210MB fat32 All good so far! But after that I couldn't rescue any more. So I've got the partition I don't care about (the one the client didn't even know existed) but not the one with important data. I tried creating a new partition starting at 210MB but parted gave me one starting at 211MB. :( Does anyone know how to solve this? -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/

On 25/11/2011, at 6:14 PM, Russell Coker wrote:
Does anyone know how to solve this?
Fire up the MacOS X Disk Utility and see if you can Repair the disk from there. All Mac-related disk work should be done via MacOS X -- I've found that parted simply destroys hfs+ volumes if you're not very, very careful. Cheers, Avi

On Fri, 25 Nov 2011, Avi Miller <avi.miller@gmail.com> wrote:
Does anyone know how to solve this?
Fire up the MacOS X Disk Utility and see if you can Repair the disk from there. All Mac-related disk work should be done via MacOS X -- I've found that parted simply destroys hfs+ volumes if you're not very, very careful.
Well my client has done all they are capable of doing with the Mac utilities. I would hope that the Linux utility can recreate the partition without issue as it's just a matter of providing indexes into the disk storage - it shouldn't involve touching the data area. If I can get it to the stage where "file -s /dev/sdd2" will recognise hfs+ then it will be fine. I guess I could drive to their office for the purpose of manually doing stuff on a Mac but I'd like to avoid that if possible. Thanks for the suggestion though. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/

x2 to what Avi is saying; parted can quite easily trash a Mac-partitioned GPT drive; there's Mac-foo it doesn't play nicely with. Did you take a backup of the partition table before fscking with it? I'd be restoring the drive back to the pre-parted state and doing what Avi suggests (you won't need to physically go there to do that; if you talk the user through enabling "Screen Sharing" through System Preferences, you can connect to it using a VNC4 client. R ----- Original Message ----- On 25/11/2011, at 6:14 PM, Russell Coker wrote:
Does anyone know how to solve this?
Fire up the MacOS X Disk Utility and see if you can Repair the disk from there. All Mac-related disk work should be done via MacOS X -- I've found that parted simply destroys hfs+ volumes if you're not very, very careful. Cheers, Avi _______________________________________________ luv-main mailing list luv-main@luv.asn.au http://lists.luv.asn.au/listinfo/luv-main

On Fri, Nov 25, 2011 at 6:14 PM, Russell Coker <russell@coker.com.au> wrote:
A client has an eSATA dock for SATA disks and he's been using a 2TB disk on his Mac. He says that he just came in one morning to see that it was claiming to be empty.
<snip> I may be a little late to this conversation but I thought I'd share my experiences. I've found a combination of the Mac Disk Utility (as others have suggested) and linux GPTfdisk (gdisk) the best tools for playing with GPT partitions to be used by OSX. gdisk is especially useful when sharing a disk between OSX & linux as unlike Disk Utility it can read & manipulate partitions that use both Apple's HFS+ and popular linux filesystems. gdisk also adds some useful features for backing up, rebuilding & modifying MBR and GPT partition tables used by OSX. While anyone familiar with command line partitioning tools should find gdisk fairly straightforward the documentation is also quite good. See here for more info http://www.rodsbooks.com/gdisk/
participants (4)
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Avi Miller
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Russell Coker
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Ryan Verner
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Tim Hamilton