Read how to recover data lost from an HFS+ drive, and how to recover a MacOS Extended drive. We have tested popular tools in various scenarios involving data loss.
HFS+ file system (Mac OS Extented)
HFS+ or Mac OS Extended is the update for the previous file system format by Mac OS known as HFS, or Hierarchical File System.
HFS+ introduced journaling, which increased reliability of data storage.
Journaled operating system keeps a log file (journal) of changes which helps to recover the hard disk quicker after failures, and accelerates the work of Time Machine.
Just as its predecessor, HFS+ uses the so-called B-tree to store a major part of metadata.
To manage the process of data allocation on the disk, HFS+ stores special service information known as metadata. The following elements are most important for the proper operation of the file system and are of special interest when searching for missing data:
- HFS boot blocks located in sectors 0 and 1.
- Volume header which is located in the second sector.
- Allocation file.
- Catalog file. The Catalog File is a B-tree that contains records for all the files and directories stored in the volume.
Recovering data from HFS+ file system is more difficult than from other file systems. One of the aspects causing difficulties is that HFS+ uses B-trees to store most volume metadata on allocation of files. After a file is removed, the B-tree is updated immediately, so the information on where the removed file was located is lost at once.
For full-scale and successful data recovery, you need to select the right software tool.
Top data recovery tools
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We have selected the best popular data recovery tools supporting HFS+ and ran some benchmark tests after erasing data on the disk. Below, we will present the test results.
For the benchmark, we have chosen the following tools: Hetman Partition Recovery, R-Studio, EaseUS Data Recovery Wizard, Disk Drill, UFS Explorer and Recuva.
As we examined the tools more closely, we had to exclude Recuva from the list as it doesn’t support HFS+ file system. So in the end, we will compare efficiency of the five specialized utilities.
We have created a test disk on the computer with Mac OS Catalina, copied some files there (photos, videos, and documents), and then removed some of the data.
We connected this disk to another computer with Windows 10, with all recovery tools already installed, and started testing them.
Testing Hetman Partition Recovery
The first tool on the list is Hetman Partition Recovery.
It recognized the test disk, the type of its file system – HFS+, and displays its name.
In this case of a simple deletion, a fast scan will suffice.
Here is the scan result: all files and folders are still on the disk, and the ones that have been removed are marked with a red cross. The disk structure and file names are retained. All the files are displayed in the preview window and available for recovery.
The program has completed this test successfully and met the challenge just as it should.
Testing RStudio
RStudio also displays the test disk, its name and file system type.
For some reason, it doesn’t display the folder 1Movie after a quick scan: most likely because the program couldn’t find it; also, some folders are shown twice and marked as deleted, though they are not. Other files are available for preview and recovery.
This tool completed the task partially as it couldn’t find one folder with a file. Generally, the final result is a little worse in comparison with Hetman Partition Recovery.
Testing EaseUS
Testing EaseUS, we can see it also displays the test disk, its name and file system type.
There is no option for a quick scan in EaseUS: as soon as you try to open the disk, it triggers an advanced scan. It may count as the first disadvantage of this product.
After the advanced scan, the result is 259 files.
The program displays all files and folders, all files can be viewed, but it is difficult to understand which elements were removed, and which are still on the disk. Also, some files are duplicated and you can’t view them.
In the end, this product managed to find all the files, both deleted and those still on the disk, but it would be more convenient to have a sort of marking to distinguish between the two types. Some files got duplicated. The program has completed this test successfully.
Testing DiskDrill
DiskDrill displays the disk size, its file system type is indicated as HFS, the disk name is missing.
With quick scan, the program failed to find the deleted data, and only displayed the information which is still on the disk. Only a deep scan is available.
Here is what the deep scan says: the disk structure is lost as well as file names, and there are some duplicates as well. They are arranged by type into various folders, and it’s hard to tell which of them were removed. Also, it’s hard to tell if the program was able to recover all data.
Videos and documents are unavailable for preview, so I can’t say for sure if they can be recovered.
This tool has coped with the task partially, and so far, we give it the last position in our rating, because some files are unavailable for preview, and the deep scan takes quite a long time.
Testing UFSExplorer
UFSExplorer is the next product to be tested.
UFSExplorer can recognize the test disk, its file system type, but fails to display the disk name.
There is no quick scan option either.
Here is what full scan shows us: deleted data is found, the disk structure and file names are retained, removed elements are marked with a different color.
Photos and videos can be previewed. All folders can be located easily. The only disadvantage is that you can’t view documents. Photos and videos have no preview issues.
Talking of document recovery, there is much to be desired.
Summing up, we can say that the tool has coped with the task partially, as it encountered difficulties in displaying documents.
After the first round of testing, the two best tools are Hetman Partition Recovery and EaseUS as they both didn’t have any issues when analysing the test disk. The only downside in EaseUS is that it lacks the quick scan option. Other utilities have minor drawbacks. RStudio failed to detect one folder with a file, while DiskDrill and UFSExplorer couldn’t preview certain files.
In the following tests, we have erased file system elements, one by one: Volume Header, Alternate Volume Header, Header Node and Index node of the second level.
Volume Header removed
In HFS+, the Volume Header is located in the second sector (from the beginning) and in the second-to-last sector (from the end of the volume), so that’s why we have erased the main header in the second sector at the beginning of the disk, then run the analysis to compare performance of the tools selected for the benchmark.
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