Disk Utility User Guide
Step 2 Create Bootable USB from macOS Install Image Click on Load DMG to import the macOS installation file into the application. Insert a USB (16G free space) and click on the 'Burn' button next to the appropriate media type.
I initially captured the OS with JAMF Composer and then used Apple System Image Utility to create a netboot image out of that DMG it creates, but to rule out variables, I just captured it directly from disk using Apple System Image Utility and I still have these problems. Next, click the Image button next to Source and point to the InstallESD.dmg file recently. DMG Canvas helps you manage the content and appearance of disk image files using helpful templates. Choose your files, create your background image using helpful controls, and click Build. Your disk image will appear in Finder exactly as you designed it. Create a NetBoot image To create your NetBoot image: Locate the disk image you created last week using AutoDMG and double click it. Make sure you let it verify.
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.
Create Netboot Image From Dmg Online
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.
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.
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␡- Creating Basic Images with SIU
This chapter is from the book
This chapter is from the book
Creating Basic Images with SIU
In this section you will learn how to create and modify basic network disk images. You can create network disk images using SIU from any Mac OS X v10.6 computer. All you need is a system with access to your source media and enough storage space to save the newly created image files. Similar to when you create cloned system images, the destination volume needs roughly two times the amount of available space as there is used space on the source volume.
Once you have created your network disk images, you can host them from a NetBoot server, as detailed in Chapter 5, “Deploying System Images.” It’s important to note that you don’t have to create the network disk image on the server where it will eventually be hosted. You can save the image to your Mac client’s system drive or an external drive, and then copy it to the appropriate location on your NetBoot server.
Create a Basic Network Disk Image
To create a basic NetBoot, NetInstall, or NetRestore image:
- Mount your source system volume.
The source system can be either Mac OS X v10.6.x or Mac OS X Server v10.6.x. The source volume can be the original installation media, a nonbooted system volume, or a disk image containing either.
- Open /Applications/Server/System Image Utility.
You will be presented with the basic NetBoot image-creation interface. System Image Utility automatically scans all mounted volumes for valid sources and lists them under Sources in the left column.
- Select the system volume you wish to make an image of from the Sources list.
- Select the appropriate button to define the type of image you want to create; NetBoot, NetInstall, or NetRestore.
- Click the Continue button once you have made your selections.
- Enter an image name and description.
The image name will be displayed by any interface that allows you to select this image, including the Server Admin application and Startup Disk preferences.
- If you intend to host this network disk image on multiple servers, select the “Image will be served from more than one server” checkbox.
Selecting this option will set the network image ID to a range that tells the NetBoot service to automatically provide load balancing if the image is shared from more than one source. If you’re not sure, simply leave the default setting, as this can be easily changed later.
- If you are creating a NetBoot or NetRestore image from installation media, you will need to configure a local administrator account.
Enter a name, short name, and password (twice) to define the new local administrator account. You can also set the account picture by clicking the image at the right.
- When you are satisfied with your network disk image settings, click the Create button.
- Agree to the software license agreement to continue with the network disk image creation process.
- When prompted, enter a name and select a location to save the network disk image.
The name you choose here is only used to set the name of the folder that contains the network disk image resources; it does not affect the image name you specified earlier.
The save location can be any writable destination that has enough space to hold a copy of your network disk image. However, if you’re creating this image on the server that will be hosting it, you can save time by choosing the NetBoot share point. The default location for the NetBoot share point is the /Library/NetBoot/NetBootSP0/ folder.
- Click the Save button and then authenticate as an administrative user to initiate the network disk image creation process.
Creating a network disk image can take from a few minutes to a few hours, depending on the size of the image source, the type of image you’re creating, and the speed of your hardware configuration. SIU will show the progress of the creation process, and you can always click the Cancel button to stop it. For a more detailed log of the creation process, choose View > Show Log.
Modifying Network Disk Images
Modifying an existing network disk image is easy, as long as you don’t need to apply a major Mac OS X update to the system volume. System updates that change the Mac OS X version—for instance, from version 10.6.1 to 10.6.2—usually replace core system components such as the UNIX kernel. Because of the special system image format of a network disk image, a major Mac OS X update installation will not properly replace these items. If you need to update the version of Mac OS X in a network disk system volume, you will have to create a new image.
Network disk images are created by SIU as folders named with the .nbi extension. The system image file that Mac computers start up from when using the NetBoot service is inside the network disk .nbi folder. Inside a NetBoot image folder you will find “NetBoot.dmg,” while inside NetInstall and NetRestore images you will find “NetInstall.dmg.” Most modifications of network disk images are as simple as mounting this read/write system image volume, applying your changes, and then ejecting the volume. NetBoot system images usually have about a gigabyte of free space for making changes, but NetInstall and NetRestore images have very little room for making changes.
Modifying the Deployable System
Standard NetInstall images created from Mac OS X installation media can technically be modified, but making any useful change is difficult because the Mac OS X installation process is not easily editable.
However, you can easily access and replace the system image that is restored by a NetRestore image. Inside the NetRestore image folder you’ll find the “NetInstall.dmg” system image; mount this image by simply double-clicking on it. You’ll note the content of this disk image is the system used to start up Mac computers via the NetBoot service. This image content also includes the prepared system restore disk image located at /Volumes/NetInstall/System/Installation/Packages/System.dmg.
Create Netboot Image From Dmg Download
If you wish to use another deployment mechanism to restore this system image, simply copy the System.dmg out of the mounted NetInstall volume and deploy it as you wish. Conversely, you can replace this disk image with any other prepared (scanned for ASR) system image. Providing the system image file is named “System.dmg” and is in the correct folder, the NetRestore process will restore that system instead.