DMG Image of Startup Disk Won't Mount — URGENT HELP NEEDED!!

I am in high-anxiety panic mode — I have lost everything on my hard drive! Please help!

This initial description will be lengthy with hopes that others have found a solution or can lend a helping hand.

Research

I have been scouring the web for a solution day and night — literally.

I have found discussions about similar, if not exactly alike, problems (e.g., http://discussions.apple.com/thread.jspa?messageID=5751143). Although they have solidified my belief that my data is definitely recoverable, I have not been successful yet.

*A Series of Unfortunate Events*

1. My MacBook Pro's Airport went out (unrelated issue), so I prepped my MBP to be sent to Apple to be fixed.

2. All data was backed up with Time Machine. Also, I booted to the Mac OS X Install Disc 1 that came with my MBP and used Disk Utility to create an image (DMG) of my entire startup disk.

3. I installed a fresh copy of Mac OS X on the hard drive and sent the MBP to Apple.

4. While the MBP was out to be worked on, I desperately needed space on my G-RAID2 so I deleted my Time Machine backups, thinking it was no big deal since I had the DMG backup. Looking back, I have +no idea+ what I was thinking.

5. When I got my MBP back, I tried to mount the DMG to access my files and got this error: "The following disk images failed to mount" with "no mountable file systems" given as Reason.

*Other Information*

My MBP has a 500 GB hard drive with two partitions, one for Mac OS X and one for Windows Vista Ultimate 64-bit (Bootcamp). The Mac OS X partition had a capacity of 414.88 GB, but with only approx. 300 GB used.

When I first tried to create the DMG, I selected New Image and used the settings "read/write" for Image Format and "none" for Encryption. However, I did not have enough free space, so I used the default settings "compressed" for Image Format and "none" for Encryption. The image was created +without any reported errors+ at a size of 226.83 GB.

*Elementary Tests*

Disk Utility
~ Can see the DMG.
~ Repair Disk returns an error: "Repairing volume failed: Unrecognized Filesystem."
~ Using Convert works, but the new image is the exact same (with the same failures).

DiskWarrior
~ Cannot see the DMG because it won't mount. This is expected given DW documentation.
~ Using File > Rebuild Disc Image... I am able to select the DMG, but I get the following error (probably resulting from being unmountable): "DiskWarrior encountered an unexpected error while attempting to rebuild the directory of the disk '/backup/Mac OS X.dmg'. Rebuilding was canceled and the disk was not modified. Restart from the DiskWarrior disc and try rebuilding again. If you report this error, please mention the error code (2150, 2)."

DropDMG
~ Able to convert the DMG to CDR, but still unmountable.

Data Rescue II (Demo) and VirtualLab Data Recovery (Free Trial)
~ Able to scan DMG and find some files, but I cannot see what the files actually are since I am using the free versions. This simply gives me hope that I don't have a useless image.

*Closing Statements*

ANYONE that can help, PLEASE do! With the insomnia this is causing, I will be here 24/7.

Thank you in advance!

Steve

MacBook Pro 17-inch: 2.5 GHz (Early 2008), Mac OS X (10.5.7), Intel Core 2 Duo, 4 GB Memory, 500 GB Hard Drive

Posted on Jun 30, 2009 11:12 PM

53 replies

Jul 1, 2009 10:22 PM in response to R C-R

R C-R –

I took your suggestion and immediately scheduled an appointment at the Apple Store (it was mentioned in the post above yours). There is no resistance by me to anything that has been recommended — I am thankful for all the help offered.

As for SuperDuper! and DiskWarrior, I concur, especially since I have thoroughly tried both, that the programs alone will not be the solution. However, I think Bob was recommending I talk to their support about the problem since they both have in-depth knowledge about the way images are constructed in Mac OS X. The worst that can happen is that they say they can't help, the best that can happen is that have seen this issue before (I own both software).

KJK555

Level 4

2,906 points

Jul 2, 2009 3:22 AM in response to Steven "Steve" Rogers

Hi Steve:
Here is a related article I stumbled upon with some things you might want to try:
http://lorenzo.yellowspace.net/corrupt-sparseimage.html
If you could ever just get hdiutil to attach it without mounting it, you could repair it with DU or
Disk Warrior.

I was playing around with some different programs, and I discovered that a program that can read iso
files can read .cdr files as well, just change the file extension from cdr to iso. I was able to read
a dmg converted to iso (cdr) in isobuster (a windows cd recovery tool). How a file as large as yours
will act when fed into that program though is anyones guess. It may choke on it, but it certainly
would be worth a try. Also since your image is compressed, I wonder how that is going to
complicate recovery? It is standard zlib compression though, so decompressing it probably
wouldn't be much of a challenge.

I use images to store my data on as well. I only use uncompressed sparsebundles with or without
encryption (as necessary) now because of the unreliability of the UDIF image format. The later
UDSB and UDSP seems to be a much more stable format for storing backups. one good reason is
they now contain two headers (one main copy and one backup) just like a regular disk volume.
If the need arises, they can be easily converted to UDIF (for volume restore purposes). I have found
CCC (Carbon Copy Cloner) eliminates the need for the convert step most of the time as it handles
the restore chore very elegantly when restoring HFS volumes. NTFS and other file systems still need
to be restored via the convert and restore method for boot volumes.

Kj

Jul 2, 2009 10:47 AM in response to KJK555

Excerpt from http://lorenzo.yellowspace.net/corrupt-sparseimage.html:

"The case handled here is: when the Finder or the terminal (hdiutil) say 'corrupt image - not when they say 'no mountable filesystems'. For the latter (whether it is an image or a real disk), there's no better tool than Disk Warrior."

Even if this is true I can't get the image to mount so DiskWarrior can't see it. But, am I wrong that it looks as if the image is attaching as disk5 (see below Terminal output)?

*hdiutil attach -nomount -noverify -noautofsck /Users/srogers/Desktop/Mac\ OS\ X.dmg*

/dev/disk5

*hdiutil attach -nomount -noverify -noautofsck -debug /Users/srogers/Desktop/Mac\ OS\ X.dmg*

calling DIHLDiskImageAttach with
mount-attempted: false
agent: hdiutil
auto-fsck: false
drive-options:
debug: true
skip-verify: true
image-options:
verbose: false
quiet: false
main-url: /Users/srogers/Desktop/Mac OS X.dmg
mount-required: false
2009-07-02 11:19:55.838 hdiutil[771:1c03] using helper tool at "/System/Library/PrivateFrameworks/DiskImages.framework/Resources/diskimages-he lper".
2009-07-02 11:19:55.860 hdiutil[771:1c03] connectToFramework
2009-07-02 11:19:55.961 hdiutil[771:1c03] sendOperationToHelper: about to ask proxy to start operation
status proc called: initialize
2009-07-02 11:19:55.981 diskimages-helper[773:1603] _imageOptions: {
"enable-keychain" = 1;
}
2009-07-02 11:19:55.983 diskimages-helper[773:1603] _driveOptions: {
"auto-fsck" = 0;
autodiskmount = 0;
"unmount-timeout" = 0;
}
2009-07-02 11:19:55.983 diskimages-helper[773:1603] DIHelperAttach: initializing framework
DILoadDriver: checking for disk image driver...DILoadDriver: DI_kextExists() returned 0x00000000 (0)...DIIsInitialized: returning NO2009-07-02 11:19:55.992 diskimages-helper[773:1603] -checkForPreviouslyAttachedImage: entry
2009-07-02 11:19:55.992 diskimages-helper[773:1603]

file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg - (null) ((null), (null)). perm=0
DIIsInitialized: returning YESDIBackingStoreNewWithCFURL: entry with
file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg
skip-permissions-check: true
DIBackingStoreInstantiatorProbe: entry
file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg
skip-permissions-check: true
DIBackingStoreInstantiatorProbe: probing interface 0 CBSDBackingStore
CBSDBackingStore::newProbe score 100 for file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg
DIBackingStoreInstantiatorProbe: probing interface 1 CBundleBackingStore
CBundleBackingStore::newProbe score -1000 for file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg
DIBackingStoreInstantiatorProbe: probing interface 2 CRAMBackingStore
CRAMBackingStore::probe: scheme "file": not ram: or ramdisk: scheme.
CRAMBackingStore::probe: score -1000 for file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg
DIBackingStoreInstantiatorProbe: probing interface 3 CCarbonBackingStore
CCarbonBackingStore::newProbe: setting initial rval to +100
CCarbonBackingStore::newProbe score 100 for file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg
DIBackingStoreInstantiatorProbe: probing interface 4 CDevBackingStore
CDevBackingStore::newProbe: not /dev/disk or /dev/rdisk (/Users/srogers/Desktop/Mac OS X.dmg).CDevBackingStore::newProbe score -1000 for
DIBackingStoreInstantiatorProbe: probing interface 5 CCURLBackingStore
CCURLBackingStore::probe: scheme is
file
CCURLBackingStore::probe: not recognized URL scheme.
CCURLBackingStore::probe: score -1000 for file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg
DIBackingStoreInstantiatorProbe: probing interface 6 CVectoredBackingStore
CVectoredBackingStore::newProbe not "vectored" scheme.
CVectoredBackingStore::newProbe score -1000 for file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg
DIBackingStoreNewWithCFURL: CBSDBackingStore
DIBackingStoreNewWithCFURL: instantiator returned 0
DIBackingStoreNewWithCFURL: returning 0x00000000
2009-07-02 11:19:55.994 diskimages-helper[773:1603] -checkForPreviouslyAttachedImage: resolving file://localhost/Users/srogers/Desktop/Mac%20OS%20X.dmg returned 0
2009-07-02 11:19:55.994 diskimages-helper[773:1603] -checkForPreviouslyAttachedImage: imageUID (
"d234881039:i50701"
) shadowUID (null)
*** testing:
0: d234881026:i958123
(null)
(null)
*** testing:
0: d234881026:i958123
(null)
(null)
*** testing:
0: d234881026:i958123
(null)
(null)
*** testing:
0: d234881039:i50701
(null)
(null)
2009-07-02 11:19:55.997 diskimages-helper[773:1603] -[DIHelperHDID initWithDiskImage:]
2009-07-02 11:19:56.000 diskimages-helper[773:1603] DIHelperAttach: attaching disk image
2009-07-02 11:19:56.001 diskimages-helper[773:1603] performAttach: entry
status proc called: attach
2009-07-02 11:19:56.002 diskimages-helper[773:1603] setMountFlags: 0x00000000
2009-07-02 11:19:56.002 diskimages-helper[773:1603] 0x00000000
2009-07-02 11:19:56.002 diskimages-helper[773:1603] performAttach: about to remountReturningDictionary
2009-07-02 11:19:56.003 diskimages-helper[773:1603] -remountReturningDictionary:
2009-07-02 11:19:56.005 diskimages-helper[773:1603] _diskAppearedCallback: disk5
2009-07-02 11:19:56.005 diskimages-helper[773:1603] : (null)
2009-07-02 11:19:56.008 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got 2BE3FA15-D4AB-4015-BAB1-CEAF3AD68451
2009-07-02 11:19:56.009 diskimages-helper[773:1603] _diskAppearedCallback: disk4s1
2009-07-02 11:19:56.010 diskimages-helper[773:1603] : (null) Apple partitionmap
2009-07-02 11:19:56.012 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got 811B8DE2-B68B-42D3-BC4E-10195F5F4FAF
2009-07-02 11:19:56.013 diskimages-helper[773:1603] _diskAppearedCallback: disk4s2
2009-07-02 11:19:56.014 diskimages-helper[773:1603] : /Users/srogers Apple_HFS
2009-07-02 11:19:56.016 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got 811B8DE2-B68B-42D3-BC4E-10195F5F4FAF
2009-07-02 11:19:56.017 diskimages-helper[773:1603] _diskAppearedCallback: disk4
2009-07-02 11:19:56.017 diskimages-helper[773:1603] : (null) Apple partitionscheme
2009-07-02 11:19:56.019 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got 811B8DE2-B68B-42D3-BC4E-10195F5F4FAF
2009-07-02 11:19:56.020 diskimages-helper[773:1603] _diskAppearedCallback: disk1
2009-07-02 11:19:56.020 diskimages-helper[773:1603] : (null) Apple partitionscheme
2009-07-02 11:19:56.022 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.023 diskimages-helper[773:1603] _diskAppearedCallback: disk1s1
2009-07-02 11:19:56.024 diskimages-helper[773:1603] : (null) Apple partitionmap
2009-07-02 11:19:56.026 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.027 diskimages-helper[773:1603] _diskAppearedCallback: disk1s3
2009-07-02 11:19:56.027 diskimages-helper[773:1603] : (null) Apple_HFS
2009-07-02 11:19:56.029 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.029 diskimages-helper[773:1603] _diskAppearedCallback: disk2
2009-07-02 11:19:56.030 diskimages-helper[773:1603] : (null) GUID partitionscheme
2009-07-02 11:19:56.032 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.032 diskimages-helper[773:1603] _diskAppearedCallback: disk2s1
2009-07-02 11:19:56.033 diskimages-helper[773:1603] : (null) C12A7328-F81F-11D2-BA4B-00A0C93EC93B
2009-07-02 11:19:56.035 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.036 diskimages-helper[773:1603] _diskAppearedCallback: disk2s2
2009-07-02 11:19:56.037 diskimages-helper[773:1603] : (null) 48465300-0000-11AA-AA11-00306543ECAC
2009-07-02 11:19:56.039 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.039 diskimages-helper[773:1603] _diskAppearedCallback: disk3
2009-07-02 11:19:56.040 diskimages-helper[773:1603] : (null) GUID partitionscheme
2009-07-02 11:19:56.042 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.043 diskimages-helper[773:1603] _diskAppearedCallback: disk3s1
2009-07-02 11:19:56.044 diskimages-helper[773:1603] : (null) C12A7328-F81F-11D2-BA4B-00A0C93EC93B
2009-07-02 11:19:56.045 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.046 diskimages-helper[773:1603] _diskAppearedCallback: disk3s2
2009-07-02 11:19:56.046 diskimages-helper[773:1603] : (null) 48465300-0000-11AA-AA11-00306543ECAC
2009-07-02 11:19:56.048 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.049 diskimages-helper[773:1603] _diskAppearedCallback: disk0
2009-07-02 11:19:56.049 diskimages-helper[773:1603] : (null) GUID partitionscheme
2009-07-02 11:19:56.051 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.052 diskimages-helper[773:1603] _diskAppearedCallback: disk0s1
2009-07-02 11:19:56.052 diskimages-helper[773:1603] : (null) C12A7328-F81F-11D2-BA4B-00A0C93EC93B
2009-07-02 11:19:56.054 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.055 diskimages-helper[773:1603] _diskAppearedCallback: disk0s2
2009-07-02 11:19:56.055 diskimages-helper[773:1603] : / 48465300-0000-11AA-AA11-00306543ECAC
2009-07-02 11:19:56.057 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.058 diskimages-helper[773:1603] _diskAppearedCallback: disk0s3
2009-07-02 11:19:56.058 diskimages-helper[773:1603] : /Volumes/Windows Vista EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
2009-07-02 11:19:56.060 diskimages-helper[773:1603] looking for UUID BBFB526F-0F26-4654-8AAE-D7908EC61B7B, got (null)
2009-07-02 11:19:56.061 diskimages-helper[773:1603] buildReturnDictionary:
2009-07-02 11:19:56.062 diskimages-helper[773:1603] adding (disk5): {
"dev-entry" = "/dev/disk5";
"potentially-mountable" = 0;
}
2009-07-02 11:19:56.063 diskimages-helper[773:1603] -remountReturningDictionary: _buildReturnDictionary returned 0
2009-07-02 11:19:56.063 diskimages-helper[773:1603] -remountReturningDictionary: kicked off hdiejectd
2009-07-02 11:19:56.064 diskimages-helper[773:1603] performAttach: remountReturningDictionary returned 0
2009-07-02 11:19:56.064 diskimages-helper[773:1603] -[DIHelperHDID dealloc:]
2009-07-02 11:19:56.065 diskimages-helper[773:1603] performAttach: returned 0
2009-07-02 11:19:56.065 diskimages-helper[773:1603] DIHelperAttach: post-processing disk image
status proc called: post-process
2009-07-02 11:19:56.066 diskimages-helper[773:1603] postProcessing: devEntry: /dev/disk5 mountPoint: (null)
2009-07-02 11:19:56.067 diskimages-helper[773:1603] performPostProcessing: returning 0.
status proc called: cleanup
2009-07-02 11:19:56.067 diskimages-helper[773:1603] DIHelperAttach performOperation: returning 0
2009-07-02 11:19:56.068 diskimages-helper[773:10b] DIHelper reportresults: reporting {
payload = {
"system-entities" = (
{
"dev-entry" = "/dev/disk5";
"potentially-mountable" = 0;
}
);
};
"result-code" = 0;
}
2009-07-02 11:19:56.068 diskimages-helper[773:1603] -decrementBackgroundThreadCount: _backgroundThreadCount is now 0.
2009-07-02 11:19:56.069 hdiutil[771:1c03] reportResultsToFramework: proxy has finished operation
2009-07-02 11:19:56.070 hdiutil[771:1c03] reportResultsToFramework: results are: {
payload = {
"system-entities" = (
{
"dev-entry" = "/dev/disk5";
"potentially-mountable" = 0;
}
);
};
"result-code" = 0;
}
2009-07-02 11:19:56.073 hdiutil[771:1c03] reportResultsToFramework: _threadResultsError is 0
2009-07-02 11:19:56.073 hdiutil[771:1c03] reportResultsToFramework: disconnecting from helper.
2009-07-02 11:19:56.174 hdiutil[771:1c03] disconnectFromHelper: removing observers
2009-07-02 11:19:56.174 hdiutil[771:1c03] disconnectFromHelper: terminating proxy
2009-07-02 11:19:56.176 diskimages-helper[773:10b] DIHelper: terminateHelper: entry.
2009-07-02 11:19:56.177 hdiutil[771:1c03] disconnectFromHelper: terminated proxy
2009-07-02 11:19:56.277 diskimages-helper[773:10b] -DIHelperAgentMaster terminateUIAgentConnection.
DIHLDiskImageAttach() returned 0
system-entities:
0:
potentially-mountable: 0
dev-entry: /dev/disk5
/dev/disk5
2009-07-02 11:19:56.280 diskimages-helper[773:10b] DIHelper dealloc.
2009-07-02 11:19:56.281 diskimages-helper[773:10b] -DIHelperAgentMaster terminateUIAgentConnection.

Jul 2, 2009 11:04 AM in response to Steven "Steve" Rogers

Does the fact that I'm receiving the message "cannot allocate memory" seem to imply anything? I.e., the image is too large to be mounted at 226.83 GB (compressed)?

Below is an extract from my post on Jul 1, 2009 9:37 PM:

*hdiutil udifxmldet /Volumes/G-RAID2/Mac\ OS\ X.dmg*

"/Volumes/G-RAID2/Mac OS X.dmg" has -1809414819546950245 bytes of embedded XML data.
hdiutil(221) malloc: * mmap(size=3985874944) failed (error code=12)
error: can't allocate region
set a breakpoint in malloc errorbreak to debug
hdiutil: udifxmldet: unable to allocate buffer to read XML data from "/Volumes/G-RAID2/Mac OS X.dmg": 12 (Cannot allocate memory).
hdiutil: udifxmldet failed - Cannot allocate memory

R C-R

Level 6

17,794 points

Jul 2, 2009 11:49 AM in response to Steven "Steve" Rogers

I think the only thing it implies is that the image file is damaged. Maybe there is more to it than that, but since I can mount good image files much larger than the available RAM, even when I'm booted from a drive with little free space, I don't think it means you need that much free memory on the drive or in RAM to mount it.

BTW, from your earlier comments & outputs, I don't think the image is actually compressed: it is shown as compressed at 1:1, meaning (I think) no compression.

Jul 2, 2009 12:32 PM in response to R C-R

I saw "UDRW", "Compressed Ratio: 1", and "Compressed: no", which to me means an uncompressed UDIF read/write image (see Terminal output I posted Jul 1, 2009 9:37 PM).

However, I know for sure that I used the default settings to create the image:
~ Image Format: compressed
~ Encryption: none

I am going to follow the exact same steps and create an image of my current startup disk to see if the problem is repeated, or if this was a onetime anomaly.

R C-R

Level 6

17,794 points

Jul 2, 2009 1:02 PM in response to Steven "Steve" Rogers

My apologies. You mentioned that you used the compressed option in your first post but I have read many posts since then & only remembered the first part of that -- incorrectly. If I'm reading it correctly now, you had 300 GB to put in the image but a bit less than that available on the target drive, or at least a compressed image of 226.83 GB fit when a 300 GB one would not.

This may have something to do with the failure, not that it helps now: OS X needs plenty of free disk space available for temporary files or it can get unstable. I don't know how much scratch space is needed to compress any large files you might have put into the archive, but I'm guessing it could be substantial. I think it is possible that during the process, the OS ran out of disk space & this contributed to the corruption of the image file.

(I know you must be thinking that the OS should warn you about this, & I agree that it should, but from what I understand it is not always possible to accurately predict the space required in advance of complex operations. If an approximation is wrong, it is sometimes possible for a situation to occur in which there is no room to run the process that posts the warning.)

You might want to take this into account when you run your test.

KJK555

Level 4

2,906 points

Jul 2, 2009 5:59 PM in response to Steven "Steve" Rogers

It looks like the drive did attach as /dev/disk5.

Attach it again and see if you can repair it with Disk Utility.
Attach it using the previously outlined procedure (hdiutil attach -nomount -noverify -noautofsck .... etc,).

to get info,
In terminal:
diskutil info /dev/disk5
This will return information about the volume if it is attached, even if not mounted.

If it is indeed attached try to repair it:
sudo diskutil repairVolume /dev/disk5

disk utility unmounts volumes before repair
as S.O.P. anyway, so if it is attached, it is fair
game for a round with D.U.

Kj

KJK555

Level 4

2,906 points

Jul 2, 2009 7:06 PM in response to Steven "Steve" Rogers

You might try converting it to a sparseimage.
can only be done at the command line:

hdiutil: convert: only a single input file can be specified
Usage: hdiutil convert -format <format> -o <outfile> [options] <image>
hdiutil convert -help
Betsy7:~ kj$ hdiutil convert -format UDSP -o /Users/kj/Desktop/kompozer-0.7.10-mac.sparseimage /Users/kj/Desktop/kompozer-0.7.10-mac.dmg
Reading Driver Descriptor Map (DDM : 0)…
Reading Apple (Apple partitionmap : 1)…
Reading disk image (Apple_HFS : 2)…
................................................................................ ........................................
Reading (Apple_Free : 3)…
Elapsed Time: 960.820ms
Speed: 43.0Mbytes/sec
Savings: 8.4%
created: /Users/kj/Desktop/kompozer-0.7.10-mac.sparseimage
Betsy7:~ kj$

Jul 2, 2009 11:34 PM in response to R C-R

The anomaly test — produced using the +exact same steps+ as the original image (see first post) — created a successful image.

However, I think the differences in the respective sizes of the images might make the test inconclusive. The image produced for the test was only 21.34 GB because I have nothing on my hard drive since reinstalling Mac OS X. The original image was over 10x larger.

I am not sure file space ran out during creation of the original image. My rationale, perhaps dubious, includes:
~ There were many GB left on the G-RAID2 after the image was created (i.e., it was not only hundreds of MB or anything close to full).
~ The disk image, which was created of my startup disk, was created on an external drive. I am not sure where the temp files are stored, but the startup disk actually had a lot of free space (greater than 100 GB).
~ Disk Utility was the only program running (from the Mac OS X Install Disc 1) and I have 4 GB memory.
~ No errors were reported before, during, or after creation — at least until I tried to mount the image, but that was after restarting and logging in to the OS.

Jul 2, 2009 11:36 PM in response to KJK555

While Terminal tries the conversion to a sparse image, here are the results of your other suggestions:

*hdiutil attach -nomount -noverify -noautofsck /Volumes/G-RAID2/Mac\ OS\ X.dmg*

/dev/disk6

*diskutil info /dev/disk6*

Device Identifier: disk6
Device Node: /dev/disk6
Part Of Whole: disk6
Device / Media Name: Apple read/write Media

Volume Name:
Mount Point:

Partition Type:
Bootable: Not bootable
Media Type: Generic
Protocol: Disk Image
SMART Status: Not Supported

Total Size: 226.8 Gi (243555893760 B) (475695105 512-byte blocks)
Free Space: 0.0 B (0 B) (0 512-byte blocks)

Read Only: No
Ejectable: Yes
Whole: Yes
Internal: No
OS 9 Drivers: No
Low Level Format: Not Supported

*sudo diskutil repairVolume /dev/disk6*

Password:
Error encountered attempting to verify/repair disk6: Unrecognized filesystem (-9958)

R C-R

Level 6

17,794 points

Jul 2, 2009 11:49 PM in response to Steven "Steve" Rogers

You have a backup copy of the file & are not trying the conversion to a sparse image on your only copy, right?

Jul 2, 2009 11:58 PM in response to R C-R

Correct. I am actually making a duplicate right now, so I haven't even got to start the process yet. Thanks for the heads up and I'll let you know ASAP the results.

romarcin

Level 1

0 points

Jul 3, 2009 5:49 AM in response to Steven "Steve" Rogers

Did you read:
http://discussions.apple.com/thread.jspa?threadID=1253428&start=0&tstart=0 ?
Year ago i had the same problem and solved it. I didn't tried this trick with converting to rw and using diskwarrior. I had uncompressed readonly image with 1 hfs extendes cases-sensitive(it actually isn't so important).

Note that after xml there may be also bit structure describing the image. In my case xml was truncated begining from section:
<key>Attributes</key>
<string>0x0050</string>
<key>Data</key>
<data>
AAA...

How many partitions did you have? Did you make backup of whole devise or of specific partition?
Please type in terminal:
tail -c 20000 broken.dmg >dmgtail
and send us dmgtail file.

read my post at: http://discussions.apple.com/thread.jspa?threadID=1253428&start=0&tstart=0
i suppose it could be harder to handle the compressed format. However we can always try.
The trick with readlonly uncompressed dmgs was that there was xml describing the 0-blocks to be omited...

Message was edited by: romarcin

Jul 3, 2009 11:22 AM in response to KJK555

The conversion from DMG to SPARSEIMAGE suffered the same problems as when I tried converting to CDR, ISO, etc.

The conversion always completes successfully, but the resultant file contains the +exact same+ size and responds the +exact same+ to all attempts at attaching, mounting, verifying, etc.

From a video background, the analogy I see is as if it is simply changing the container file while leaving the video unchanged, such as going from MKV to M2TS.

Here is the output from Terminal:

*hdiutil convert -format UDSP -o /Test/Mac\ OS\ X.sparseimage /Volumes/G-RAID2/Backup/Mac\ OS\ X.dmg*

Reading whole disk (unknown partition : 0)…
................................................................................ ................................................................................ ...............
Elapsed Time: 1h 45m 04.323s
Speed: 36.8Mbytes/sec
Savings: 0.0%
created: /Test/Mac OS X.sparseimage

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DMG Image of Startup Disk Won't Mount — URGENT HELP NEEDED!!