Having a virtual machine running macOS opens up a lot of opportunities for learning. If you are into security, you can set up a VM for your security lab. Or if you want to learn networking or kernel debugging, it is also helpful to use a VM. The other option is risk breaking your work machine in your experiments (not fun). To build our VM, we need to use Disk Images, another topic that is useful in other areas.
- Apple Sparse Bundle Disk Image Media Markt
- Sparse Image Vs Sparse Bundle
- Apple Sparse Bundle Disk Image Media Free
A Sparse Bundle is an intelligent disk image, created by Mac OS X Leopard, that is capable of growing and/or shrinking as needed. For example, a 60 GB.sparsebundle containing only a 5 MB file would not be 60 GB - it would just be 5 MB. These files are used in both FileVault and Time Machine under OS X Leopard. TransMac Crack is the best application to open Mac APFS, HFS format disk drives, and dmg files from Windows. It also helps you to open flash drives. Further, it also used for CD/DVD/Blu-ray media, HD floppies, dmg part, sparse bundle, and sparse image files. To encrypt the disk image, click the Encryption pop-up menu, then choose an encryption option. Click the Partitions pop-up menu, then choose a partition layout. Click the Image Format pop-up menu, then choose an option: Sparse bundle disk image: Same as a sparse disk image (below), but the directory data for the image is stored differently. Uses the.sparsebundle file extension. There are two main types of disk image: regular images, which include not only the data stored in them but also all free space, and sparse images/bundles which only store the data without any free space. Create a normal 10 GB disk image to contain 1 GB of files, and that.dmg file will be 10 GB in size, even though most of the file is empty. Creating the Disk Image. Open Disk Utility; Click on New Image; Set a large enough size for the disk image. Ensure that the Format is 'Mac OS X Extended (Journaled)' (in other words, this will be HFS+, the Mac's native filesystem) and the Image Format is 'sparse bundle disk image'.
Both topics are interesting, and we can combine them. In this post, I'll show you the basics of working with Disk Images and also as an example we are going to create an ISO image to build our macOS Catalina VM using VirtualBox.
There's a lot of information so let's get started.
Apple Sparse Bundle Disk Image Media Markt
NOTE: We need to download the macOS Catalina installer from the AppStore, it's around 9Gb, so It'll take some time to download. Better start now while we learn about Disk Images.
Table of Contents
Sparse Image Vs Sparse Bundle
We'll learn by making, so let's start by creating a folder that we'll use as the base for our image.
Let's add some content to our folder:
Ok, this is going to be our simple image structure:
We are going to use hdiutil. This tool uses the DiskImages.framework for. well, manage disk images. Or at least that is what its man page says. But I couldn't find any documentation on the DiskImages.framework so I assume it's a private framework. If you know anything about it, let me know. In the meantime, I encourage you to read the man page hdiutil(1) for more information.
Alright, that should have created miapplicacion.dmg image in your desktop. We can now delete the ~/Desktop/myapp, we don't need it anymore.
We can now mount the image. We can do that by clicking it using the Finder, or by using hdiutil again. I'll use hdiutil so we get more comfortable using it.
https://rdiu.over-blog.com/2021/01/pcdj-dex-3-9-0-10-dj-software-pdf.html. That will mount our image in /Volumes/myapp. I purposefully gave different names to the dmg and the image so you can see which one will be used when mounted.
If you check the newly mounted image, you'll see our hello.txt with the content Hola, mundo!.
Now you can eject it from the Finder or use hdiutil again. As you probably imagined, I'll show you how to do it with hdiutil.
You can use the name of the volume or the device, in my case:
We create the image using a source folder. We could also have created an empty image and then add content to it. Let's see how to do that.
That create s new image of ten megabytes of space. To work with that image, we need to mount it. We are going to mount it but without including its filesystem.
DANGER, WILL ROBINSON! PLEASE MAKE SURE YOU ARE POINTING TO THE CORRECT DEVICE, ELSE YOU CAN LOSE DATA! I WON'T BE RESPONSIBLE FOR ANYTHING YOU DO WITH THE INSTRUCTIONS I POST HERE, TREAD CAREFULLY.
In my computer the image is mounted in /dev/disk3 it might use a different one on your computer so make sure you refer to the correct one or BAD THINGS WILL HAPPEN.
Why did we mount our image this way? Well, we did it so we can format the volume using diskutil. Let's do that.
Now we can add some content to that Image.
Now we can eject the volume.
And now you can mount it again, and you'll see your howdy.txt file. The images we've created are Read/Write. We can also convert it to a read-only image:
You can see all the supported formats in the man page. Here is the list in mine:
Now if we mount our new image and try to write to it we'll get an error:
Alright, that should give us enough background on Disk Images (.dmg) to build our ISO image for Catalina. Let's do that now.
Since Mac OS X Lion (10.7 - released in 2011), Apple decided to no longer distribute an installation DVD, it provides the installer as an application that can be downloaded via the AppStore. This installer application contains the base system for installation and also a Recovery image that includes a basic OS implementation that is used at boot time. When you boot to the Recovery volume, you can use it to restore and/or install the operating system. You can read more on This detailed article on AFP548.
The idea is to extract all the parts from the Install macOS Catalina.app application bundle to build our ISO. I'm going to use Jeff Geerling's macOS VirtualBox VM script as a basis. It is similar to the instructions in Kedy Liu's article on macOS Kernel Debugging.
We are going to mainly focus on the InstallESD.dmg and BaseSystem.dmg images that come inside the application installer to generate an ISO image.
If you are not familiar with the ISO format, an ISO image is the image format used on an optical disk. It is the format used by DVD, CD, or Blue-ray Disc. In the past, it was common to use CDs as the media to install the operating systems. VirtualBox supports that format. We plan to create an ISO image from the installer.
Let's begin.
After the AppStore download is complete, you'll be able to find the Install macOS Catalina.app inside your /Applications/ directory.
I'll be using macOS Catalina as an example, but as long as you have the installer of any OS newer than 10.7, the process should be similar.
http://aktxamc.xtgem.com/Blog/__xtblog_entry/19202742-brian-j.-enquist-for-ecol596-spring-2012-phylocom-notes-for-mac#xt_blog. Navigate to the /Applications/Install macOS Catalina.app/Contents/SharedSupport/ directory, and list the files:
Excellent, we have the BaseSystem.dmg and the InstallESD.dmg. Inside the InstallESD.dmg we'll find the installer that uses the BaseSystem image to install the OS.
To extract the installer we'll need to mount the InstallESD.dmg image.
The BaseSystem.dmg has an image formatted in HFS. We can create an empty image as we did in the last example of the previous section. Then we can 'restore' the BaseSystem image in the newly created image. It sounds confusing, but you'll understand it better when we begin doing it.
In my computer the image is mounted in /dev/disk3 it might use a different one on your computer so make sure you refer to the correct one or BAD THINGS WILL HAPPEN.
Why did we mount our image this way? Well, we did it so we can format the volume using diskutil. Let's do that.
Now we can add some content to that Image.
Now we can eject the volume.
And now you can mount it again, and you'll see your howdy.txt file. The images we've created are Read/Write. We can also convert it to a read-only image:
You can see all the supported formats in the man page. Here is the list in mine:
Now if we mount our new image and try to write to it we'll get an error:
Alright, that should give us enough background on Disk Images (.dmg) to build our ISO image for Catalina. Let's do that now.
Since Mac OS X Lion (10.7 - released in 2011), Apple decided to no longer distribute an installation DVD, it provides the installer as an application that can be downloaded via the AppStore. This installer application contains the base system for installation and also a Recovery image that includes a basic OS implementation that is used at boot time. When you boot to the Recovery volume, you can use it to restore and/or install the operating system. You can read more on This detailed article on AFP548.
The idea is to extract all the parts from the Install macOS Catalina.app application bundle to build our ISO. I'm going to use Jeff Geerling's macOS VirtualBox VM script as a basis. It is similar to the instructions in Kedy Liu's article on macOS Kernel Debugging.
We are going to mainly focus on the InstallESD.dmg and BaseSystem.dmg images that come inside the application installer to generate an ISO image.
If you are not familiar with the ISO format, an ISO image is the image format used on an optical disk. It is the format used by DVD, CD, or Blue-ray Disc. In the past, it was common to use CDs as the media to install the operating systems. VirtualBox supports that format. We plan to create an ISO image from the installer.
Let's begin.
After the AppStore download is complete, you'll be able to find the Install macOS Catalina.app inside your /Applications/ directory.
I'll be using macOS Catalina as an example, but as long as you have the installer of any OS newer than 10.7, the process should be similar.
http://aktxamc.xtgem.com/Blog/__xtblog_entry/19202742-brian-j.-enquist-for-ecol596-spring-2012-phylocom-notes-for-mac#xt_blog. Navigate to the /Applications/Install macOS Catalina.app/Contents/SharedSupport/ directory, and list the files:
Excellent, we have the BaseSystem.dmg and the InstallESD.dmg. Inside the InstallESD.dmg we'll find the installer that uses the BaseSystem image to install the OS.
To extract the installer we'll need to mount the InstallESD.dmg image.
The BaseSystem.dmg has an image formatted in HFS. We can create an empty image as we did in the last example of the previous section. Then we can 'restore' the BaseSystem image in the newly created image. It sounds confusing, but you'll understand it better when we begin doing it.
Let's begin by creating the destination image. I'll show you the command first and after I'll explain what it does.
We are creating a sparse image. The sparse image type means that the image we create will only take as much space as the content we put on it, with the limit of 9 Gigabytes that we set. The layout indicates the partition table's layout for the created volume. We are stating that we want a single entry. The partition table layout can be split in multiple /dev entries. For example, we could have one for the GUID Partition Table (GPT), and the other partitions have the data. With the SPUD layout, we will only have one /dev entry. If you want to learn more visit the following links about Apple partition Map and GUID Partition Table.
We also define the file system type to be HFS+J. The BaseSystem.dmg disk image is also in HFS, so that is why we choose it (also because hdiutil can only resize HFS).
Ok, now you can run the command to create the sparse image. I'm showing you the command again:
Let's mount it so we can work on it.
Now we are going to copy the BaseSystem.dmg image into our /Volume/install_build image.
To copy the image we are going to use the asr command (you can check the man page asr(8) for more details).
Alright, this will copy the Base System inside our volume /Volumes/install_build, so It will erase our /Volumes/install_build and replace it with /Volumes/macOS Base System/. If you check our /Volumes/ you'll see it there.
The BaseSystem.dmg Acrobat reader apple pencil. includes symbolic links to the Packages directory. When we are installing the OS with the application that symbolic link will exist. But in our case, that symbolic link points to the wrong place. You can verify this by listing the contents in /Volumes/macOS Base System/System/Installation/.
What we are going to do is replace that symbolic link with the contents of the Packages directory we find in our InstallESD.dmg that we mounted in /Volumes/install_app. We can rm and then cp Or we can use the ditto(1) command.
Apple Sparse Bundle Disk Image Media Free
We also need to copy some installer dependencies, i.e. BaseSystem.chunklist and BaseSystem.dmg, and add them to the image. We find those two files in /Applications/Install macOS Catalina.app/Contents/SharedSupport, let's list that directory:
Ok, now that we know where they are let's copy them to our image volume:
That's it. That is our image ready. Let's now unmount the images, clean up and prepare to convert our installation image to a read-only image.
Let's clean up and resize to free up any extra space. hdiutil can only resize filesystems of type HFS+. Again, read the man page for additional information on resize (hdiutil(1)). We can obtain the current size of the image using the -limit argument:
NOTE: as pointed out by quantum_libet we can simplify by using the size -min parameter, this is much more clean than my previous solution. Thanks for the tip!
Now we are ready to convert the image to a CD-R export image. You can see how to do this in the man page in the examples section (hdiutil(1), as you can see a lot of information in the man page).
And that's it. We now have the Catalina.iso. We can use our ISO in VirtualBox to create our macOS Virtual machine!
Alright, now for the ugly part. VirtualBox doesn't support APFS in their UEFI boot loader (you can read the discussion in VirtualBox's forum). Luckily Alexander Willner created a handy script with the name runMacOSinVirtualBox that automates the creation of a VirtualBox VM that works. The script creates a bootable partition that can be used to boot macOS while we wait for VirtualBox to support APFS.
His script can also be used to create an ISO, but we have already done that, so no need.
Ok clone or download his script and run it.
Now we can go to VirtualBox, and add our ISO image as an optical drive to the newly created VM.
Go to: Settings > Storage > Add New Optical Drive and select our newly created Catalina.iso.
Now you can start the VM. Now select Disk Utility and format your macOS partition using APFS (click Erase and select APF). After the formatting is complete, quit Disk Utility and click 'Reinstall macOS'. Follow and complete the installation process.
Congratulations! You now have Catalina running on VirtualBox :).
We could have copy/paste or cloned the scripts created by Alexander Willner, Jeff Greeling or Kedy Liu. But I believe it's helpful to understand any code we use so we can build on top of that knowledge. How to print screen on apple mac.
We learned how to work with Disk Images. As you can see, it is a convenient topic to understand. For example, some people distribute their applications outside the AppStore using .dmgs.
And also you now have a VM that you can use to build your security lab or to explore Kernel Debugging.
Ok, that's it for this post. I hope that you found this post useful :).
I also would like to thank all the people that very openly share their knowledge and help us understand how things work. I think the metaphor standing on the shoulders of giants, is quite apt.
Thank you.
Most of the links I'll add here are already in the post but for convenience I'll add them again.
- A detailed article on the structure of the macOS Installation App - AFP548.
- Jeff Geerling's macOS VirtualBox VM script.
- Kedy Liu's article on macOS Kernel Debugging.
- Alexander Willner handy script runMacOSinVirtualBox.
- Documentation on Apple partition Map and GUID Partition Table.
Disk Utility User Guide
You can use Disk Utility to create a disk image, which is a file that contains other files and folders.
Note: You can burn information to a CD or DVD using the Burn command in the Finder. See Burn CDs and DVDs.
Create a blank disk image for storage
You can create an empty disk image, add data to it, then use it to create disks, CDs, or DVDs.
In the Disk Utility app on your Mac, choose File > New Image > Blank Image.
Enter a filename for the disk image, add tags if necessary, then choose where to save it.
This is the name that appears in the Finder, where you save the disk image file before opening it.
In the Name field, enter the name for the disk image.
This is the name that appears on your desktop and in the Finder sidebar, after you open the disk image.
In the Size field, enter a size for the disk image.
Click the Format pop-up menu, then choose the format for the disk:
If the disk image will be used with a Mac that has a solid state drive (SSD) and uses macOS 10.13 or later, choose APFS or APFS (Case-sensitive).
If the disk image will be used with a Mac with macOS 10.12 or earlier, choose Mac OS Extended (Journaled) or Mac OS Extended (Case-sensitive, Journaled).
If the disk image will be used with a Mac or Windows computer and is 32 GB or less, choose MS-DOS (FAT); if it's over 32 GB, choose ExFAT.
To encrypt the disk image, click the Encryption pop-up menu, then choose an encryption option.
Click the Partitions pop-up menu, then choose a partition layout.
Click the Image Format pop-up menu, then choose an option:
Sparse bundle disk image: Same as a sparse disk image (below), but the directory data for the image is stored differently. Uses the .sparsebundle file extension.
Sparse disk image: Creates an expandable file that shrinks and grows as needed. No additional space is used. Uses the .sparseimage file extension.
Read/write disk image: Allows you to add files to the disk image after it's created. Uses the .dmg file extension.
DVD/CD master: Changes the size of the image to 177 MB (CD 8 cm). Uses the .cdr file extension.
Click Save, then click Done.
Disk Utility creates the disk image file where you saved it in the Finder and mounts its disk icon on your desktop and in the Finder sidebar.
In the Finder, copy your files to the mounted disk image, then eject it.
Restore the disk image to a disk.
For more information about disk image types, see the manual (man) page for hdiutil.
Create a disk image from a disk or connected device
You can create a disk image that includes the data and free space on a physical disk or connected device, such as a USB device. For example, if a USB device or volume is 80 GB with 10 GB of data, the disk image will be 80 GB in size and include data and free space. You can then restore that disk image to another volume.
In the Disk Utility app on your Mac, select a disk, volume, or connected device in the sidebar.
Choose File > New Image, then choose 'Image from [device name].'
Enter a filename for the disk image, add tags if necessary, then choose where to save it.
This is the name that appears in the Finder, where you save the disk image file before opening it.
Macbooster 3 0 7 download free. Click the Format pop-up menu, then choose an option:
Read-only: The disk image can't be written to, and is quicker to create and open.
Compressed: Compresses data, so the disk image is smaller than the original data. The disk image is read-only.
Read/write: Allows you to add files to the disk image after it's created.
DVD/CD master: Can be used with third-party apps. It includes a copy of all sectors of the disk image, whether they're used or not. When you use a master disk image to create other DVDs or CDs, all data is copied exactly.
To encrypt the disk image, click the Encryption pop-up menu, then choose an encryption option.
Click Save, then click Done.
Disk Utility creates the disk image file where you saved it in the Finder and mounts its disk icon on your desktop and in the Finder sidebar.
Important: Don't create a disk image of a disk that you believe to be failing or that contains corrupted information. The disk image may not serve as a reliable backup.
For technical information about creating a restore disk image, see the Apple Software Restore (ASR) manual (man) page.
Create a disk image from a folder or connected device
You can create a disk image that contains the contents of a folder or connected device, such as a USB device. This method doesn't copy a device's free space to the disk image. For example, if a USB device or volume is 80 GB with 10 GB of data, the disk image will be 10 GB in size and include only data, not free space. You can then restore that disk image to another volume.
In the Disk Utility app on your Mac, choose File > New Image, then choose Image from Folder.
Select the folder or connected device in the dialog that appears, then click Open.
Enter a filename for the disk image, add tags if necessary, then choose where to save it.
This is the name that appears in the Finder, where you save the disk image file before opening it.
To encrypt the disk image, click the Encryption pop-up menu, then choose an encryption option.
Click the Image Format pop-up menu, then choose an option:
Read-only: The disk image can't be written to, and is quicker to create and open.
Compressed: Compresses data, so the disk image is smaller than the original data. The disk image is read-only.
Read/write: Allows you to add files to the disk image after it's created.
DVD/CD master: Can be used with third-party apps. It includes a copy of all sectors of the disk image, whether they're used or not. When you use a master disk image to create other DVDs or CDs, all data is copied exactly.
Hybrid image (HFS+/ISO/UDF): This disk image is a combination of disk image formats and can be used with different file system standards, such as HFS, ISO, and UDF.
Click Save, then click Done.
Disk Utility creates the disk image file where you saved it in the Finder and mounts its disk icon on your desktop and in the Finder sidebar.
For technical information about creating a restore disk image, see the Apple Software Restore (ASR) manual (man) page.
Create a secure disk image
If you have confidential documents that you don't want others to see without your permission, you can put them in an encrypted disk image.
Note: If you want to protect the contents of the system disk, turn on FileVault using the FileVault pane of Security & Privacy Preferences.
In the Disk Utility app on your Mac, choose File > New Image > Blank Image.
Enter a filename for the disk image, add tags if necessary, then choose where to save it.
This is the name that appears in the Finder, where you save the disk image file before opening it.
In the Name field, enter the name for the disk image.
This is the name that appears on your desktop and in the Finder sidebar, after you open the disk image.
In the Size field, enter a size for the disk image.
Click the Format pop-up menu, then choose a format:
If you're using the encrypted disk image with a Mac computer using macOS 10.13 or later, choose APFS or APFS (Case-sensitive).
If you're using the encrypted disk image with a Mac computer using macOS 10.12 or earlier, choose Mac OS Extended (Journaled) or Mac OS Extended (Case-sensitive, Journaled).
Click the Encryption pop-up menu, then choose an encryption option.
Enter and re-enter a password to unlock the disk image, then click Choose.
WARNING: If you forget this password, you won't be able to open the disk image and view any of the files.
Use the default settings for the rest of the options:
Click the Partitions pop-up menu, then choose Single partition - GUID Partition Map.
Click the Image Format pop-up menu, then choose 'read/write' disk image.
Click Save, then click Done.
Disk Utility creates the disk image file where you saved it in the Finder and mounts its disk icon on your desktop and in the Finder sidebar.
In the Finder , copy the documents you want to protect to the disk image.
If you want to erase the original documents so they can't be recovered, drag them to the Trash, then choose Finder > Empty Trash.
When you're finished using the documents on the secure disk image, be sure to eject the disk image. As long as it's available on your desktop, anyone with access to your computer can use the documents on it.
To access the data in a disk image, double-click it. It appears on your desktop, and you can add, remove, and edit files on it just as you would with a disk.
