Build DMG from APFS Recovery volume
| Originator: | adrian.kubisztal | ||
| Number: | rdar://33208209 | Date Originated: | 10 July 2017 |
| Status: | Closed | Resolved: | |
| Product: | macOS 10.13 APFS | Product Version: | 10.13 |
| Classification: | Reproducible: | Yes |
Area: Disk Utility Summary: I would like to create dmg from APFS Recovery volume. Command: hdiutil create /Users/admin/Recovery.dmg -srcdevice /dev/disk1s3 Is not working in this case. /dev/disk1s3 is recovery volume. Steps to Reproduce: 1. Use 10.13 APFS 2. Run terminal 3. sudo hdiutil create /Users/admin/Recovery.dmg -srcdevice /dev/disk1s3 -gid 20 -mode 755 -puppetstrings -format UDZO Expected Results: Operation should create Recover.dmg Observed Results: hdiutil: create failed - No such file or directory -verbose: CDevBackingStore::openDataFork open() failed: Operation not permitted MESSAGE:Attaching… Error -1 (Undefined error: 0). MESSAGE:Finishing… DIHLDiskImageCreate() returned -1 hdiutil: create: returning -1 hdiutil: create failed - No such file or directory -debug CBSDBackingStore::setPermission: opening /dev/rdisk1s3 CBSDBackingStore::OpenLockFriendly: mapping flags 0x00000000 -> 0x00000014 (locks are MANDATORY) CBSDBackingStore:OpenLockFriendly: could not open with lock 1 CDevBackingStore::setPermission: CBSDBackingStore could not grant permission. checking stat results instead. /dev/rdisk1s3 : crw-r----- CDevBackingStore::newWithCFURL: granting read-only access CDevBackingStore::setURL_Permissions_and_OpenFile: permission granted kDI_PERM_READONLY. CDevBackingStore::openDataFork open() failed: Operation not permitted DIBackingStoreNewWithCFURL: instantiator returned 4294967295 DIBackingStoreNewWithCFURL: returning -1 DIResolveURLToBackingStore: unable to resolve to any backing store class. -1. DIResolveURLToDiskImage: resolving backing store/file encoding failed. -1. Version: 10.13 second beta, APFS file system Notes: disk1s3 is recovery volume. This command is working without any problem on HFS 10.12 Apple Answer: You cannot create a diskimage from any APFS volume. It has to be created from an APFS container. This is because APFS stores all its metadata for all volumes inside the container and using -srcdevice with a particular volume does not make sense. The error that we see in this case is the expected behavior. As an alternative, “-srcfolder <path to mounted recovery volume>” can be used. This just does a file by file copy of the recovery volume contents while creating the new diskimage. We are now closing this bug report. If you have questions or comments about the resolution, please update your bug report with that information so we can respond.
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You cannot create a diskimage from any APFS volume. It has to be created from an APFS container. This is because APFS stores all its metadata for all volumes inside the container and using -srcdevice with a particular volume does not make sense.
The error that we see in this case is the expected behavior.
As an alternative, “-srcfolder” can be used. This just does a file by file copy of the recovery volume contents while creating the new diskimage.
We are now closing this bug report.
If you have questions or comments about the resolution, please update your bug report with that information so we can respond.