diskimgr provides a simple GUI-based workflow for making disk images of digital media, such as floppy disks, Flash drives and harddisks. It wraps around the dd and ddrescue tools. After the imaging is done it also generates a checksum file with SHA-512 hashes of the extracted files.
Diskimgr is currently only available for Linux. So far it has been tested with Ubuntu 18.04 LTS (Bionic) and Linux Mint 18.3, which is based on Ubuntu 16.04 (Xenial). In addition it has the following dependencies:
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Python 3.2 or more recent (Python 2.x is not supported)
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Tkinter. If tkinter is not installed already, you need to use the OS's package manager to install (there is no PyInstaller package for tkinter). If you're using apt this should work:
sudo apt-get install python3-tk -
dd, which is part of the GNU Core Utilities.
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ddrescue, which can be installed using:
sudo apt install gddrescue
By default, running dd on a Linux system requires root access. To allow a non-root user to run dd, you must give them the permissions to do so by adding the user to the disk group. You can do this with the command below (replace $USER with the name of the user who will be using diskimgr):
sudo adduser $USER disk
The user is now added to the 'disk' system group. Now log out, and then log in again for the changes to take effect.
For a global (all-users) installation run the following command:
sudo pip3 install diskimgr
Then run:
sudo diskimgr-config
If all goes well this should result in the following output:
INFO: writing configuration file /etc/diskimgr/diskimgr.json
INFO: creating desktop file /usr/share/applications/diskimgr.desktop
INFO: diskimgr configuration completed successfully!
Use the following command for a single-user installation:
pip3 install --user diskimgr
Then run:
~/.local/bin/diskimgr-config
Result:
INFO: writing configuration file /home/johan/.config/diskimgr/diskimgr.json
INFO: creating desktop file /home/johan/.local/share/applications/diskimgr.desktop
INFO: diskimgr configuration completed successfully!
diskimgr is now ready to roll!
You can start diskimgr from the OS's main menu (in Ubuntu 18.04 the diskimgr item is located under System Tools). Depending on your distro, you might get an "Untrusted application launcher" warning the first time you activate the shortcut. You can get rid of this by clicking on "Mark as Trusted". On startup the main diskimgr window appears:
Use the Select Output Directory button to navigate to an (empty) directory where the output files are to be stored. The interface allows you to specify the following options:
| Option | Description |
|---|---|
| Block Device | Select the medium (device) you want to image from the drop-down list. Press the Refresh button to refresh the items in the drop-down list |
| Block size | This sets the size of the buffer (in bytes) that is used by dd / ddrescue default: 512). |
| Read method | The method (application) that is used to read the medium (default: dd). |
| Retries | Maximum number of retries (setting only has effect with ddrescue) (default: 4). |
| Direct disc mode | Check this option to read a medium in direct disc mode (setting only has effect with ddrescue) (disabled by default). |
| Auto-retry with ddrescue on dd failure | This checkbox controls the behaviour with media that result in read errors with dd. If checked, diskimgr will automatically re-try such a medium with ddrescue. Otherwise, diskimgr will first display a confirmation dialog. |
| Load existing metadata | Loads Prefix, Extension, Identifier, Description and Notes values (see below) from an existing metadata file in the output directory that was created by a previous diskimgr session. Useful for re-running media that were previously interrupted or unfinished. If no metadata file can be found, diskimgr will display an error, and the fields can be entered manually |
| Prefix | Output prefix (default: disc). |
| Extension | Output file extension (default: img). |
| Identifier | Unique identifier. You can either enter an existing identifier yourself, or press the UUID button to generate a Universally unique identifier. |
| Description | A text string that describes the medium (e.g. a title that is written on the label of a floppy disk). |
| Notes | Any additional info or notes you want to record with the medium. |
Press the Start button to start imaging a medium. You can monitor the progress of the extraction procedure in the progress window:
Note that the screen output is also written to a log file in the output directory. A prompt appears when the imaging is finished:
If the imaging finished without any errors, the output directory now contains the following files:
Here, ks.img is the created ISO image; checksums.sha512 contains the SHA512 checksums of the image, metadata.json contains some basic metadata and diskimgr.log is the log file.
If dd's attempt to read the disc resulted in any errors, diskimgr prompts the user to try again with ddrescue:
After clicking Yes, diskimgr will move the disc image that was created by dd to a subdirectory dd-failed, and then start ddrescue. If ddrescue also exits with any errors, you will see this dialog:
From ddrescue's output, you can see that 106 kB of data could not be recovered (value of errsize variable). After pressing Yes, you can do one or more additional passes with ddrescue. For instance, you can activate Direct Disc mode, or select another floppy drive. Press the Start button again to start reading the medium. Importantly, this won't overwrite the existing image, but it will update it with any additional data that can be rescued from the medium. As an example, below is the result of the second ddrescue pass, where Direct Disc mode was activated:
In this case ddrescue still reports a read error, but now errsize is reduced from 106 kB to just 512 bytes, which means that only one sector could not be recovered.
Note that ddrescue runs result in an additional mapfile ($prefix.map). The map file contains information about the recovery status of data blocks, which allows ddrescue to resume previously interrupted recovery sessions.
In general dd is the preferred tool to read a floppy disk, flash drive or harddisk. However, dd does not cope well with media that are degraded or otherwise damaged. Because of this, the suggested workflow is to first try reading the medium with dd. If this results in any errors, try ddrescue. If you check the Auto-retry box, diskimgr will automatically launch ddrescue if the initial attempt to read the medium with dd failed (i.e. it will not display the confirmation dialog).
It is possible to run multiple subsequent passes with ddrescue. If ddrescue fails with errors, it sometimes helps to re-run it in Direct disc mode (which can be selected from diskimgr's interface). The results can sometimes be further improved by running multiple ddrescue passes with different reader devices (e.g. a few USB-connected floppy drives).
Press the Interrupt button to interrupt any running dd or ddrescue instances. This is particularly useful for ddrescue runs, which may require many hours for media that are badly damaged. Note that interrupting ddrescue will not result in any data loss. Interrupting dd will generally result in an unreadable image file.
Follow these steps to resume a ddrescue run that was previously interrupted:
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After launching diskimgr, set the output directory to the directory of the interrupted run.
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Set Read method to ddrescue.
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Click on the Load existing metadata button; this loads the previously entered Prefix, Extension, Identifier, Description and Notes values.
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Hit the Start button. Now ddrescue will simply pick up on where the interrupted run stopped.
The file metadata.json contains metadata in JSON format. Below is an example:
{
"acquisitionEnd": "2019-04-04T17:53:11.489543+02:00",
"acquisitionStart": "2019-04-04T17:52:29.692731+02:00",
"autoRetry": false,
"blockDevice": "/dev/sdb",
"checksumType": "SHA-512",
"checksums": {
"ks.img": "79a17d3fa536b8fa750257b01d05124dadb888f1171e9ca5cc3398a2c16de81b1687b52c70135b966409a723ef5f3960536a6e994847c5ebe7d5eaffefa62dc7"
},
"description": "KS metingen origineel",
"diskimgrVersion": "0.1.0b1",
"extension": "img",
"identifier": "5b159d32-56f1-11e9-9abb-2c4138b5272c",
"interruptedFlag": false,
"maxRetries": "4",
"notes": "",
"prefix": "ks",
"readCommandLine": "dd if=/dev/sdb of=/home/bcadmin/test/1/ks.img bs=512 conv=notrunc",
"readMethod": "dd",
"readMethodVersion": "dd (coreutils) 8.28",
"rescueDirectDiscMode": false,
"successFlag": true
}Most of these fields are self-explanatory, but the following need some further explanation:
- interruptedFlag is a Boolean flag that is true if dd or ddrescue were interrupted, and false otherwise.
- successFlag is a Boolean flag that is true if the medium was imaged without any problems, and false otherwise.
Diskimgr's internal settings (default values for output file names, the optical device, etc.) are defined in a configuration file in Json format. For a global installation it is located at /etc/diskimgr/diskimgr.json; for a user install it can be found at ~/.config/diskimgr/diskimgr.json. The default configuration is show below:
{
"autoRetry": "False",
"blockSize": "512",
"checksumFileName": "checksums.sha512",
"defaultDir": "",
"extension": "img",
"logFileName": "diskimgr.log",
"metadataFileName": "metadata.json",
"prefix": "disc",
"rescueDirectDiscMode": "False",
"retries": "4",
"timeZone": "Europe/Amsterdam"
}You can change diskimgr's default settings by editing this file. Most of the above settings are self-explanatory, with the exception of the following:
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autoRetry: this flag sets the default value of the Auto-retry checkbox.
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defaultDir: this allows you to change the default file path that is opened after pressing Select Output Directory. By default diskimgr uses the current user's home directory. However, if defaultDir points to a valid directory path, that directory is used instead.
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timeZone: time zone string that is used to correctly format the acquisitionStart and acquisitionEnd date/time strings. You can adapt it to your own location by using the TZ database name from this list of tz database time zones.
If you accidentally messed up the configuration file, you can always restore the original one by running the diskimgr-config tool again.
To remove diskimgr, first run the diskimgr-config with the --remove flag to remove the configuration file and the start menu and desktop files. For a global install, run:
sudo diskimgr-config --remove
For a user install, run:
~/.local/bin/diskimgr-config --remove
The resulting output (shown below for a user install):
INFO: removing configuration file /home/johan/.config/diskimgr/diskimgr.json
INFO: removing configuration directory /home/johan/.config/diskimgr
INFO: removing desktop file /home/johan/.local/share/applications/diskimgr.desktop
INFO: diskimgr configuration completed successfully!
Then remove the Python package with following command (global install):
sudo pip3 uninstall diskimgr
For a user install use this:
pip3 uninstall diskimgr
Written by Johan van der Knijff. Some parts of the code that processes ddrescue's terminal output were adapted from DDRescue-GUI by Hamish McIntyre-Bhatty.
Diskimgr is released under the Apache License 2.0.