Imaging and Cloning Volumes Using ASR

You can use Apple Software Restore (ASR) to copy a disk image onto a volume or prepare existing disk images with checksum information for faster copies. ASR can perform file copies, in which individual files are restored to a volume unless an identical file is already there, and block copies, which restore entire disk images. The asr utility doesn’t create the disk images. You can use hdiutil to create disk images from volumes or folders.

You must run ASR as the root user or with sudo root permissions. You cannot use ASR on read/write disk images.

To image a boot volume:

1Install and configure Mac OS X on the volume as you want it.

2Restart from a different volume.

3Make sure the volume you’re imaging has permissions enabled.

4Use hditutil to make a read-write disk image of the volume.

5Mount the disk image.

6Remove cache files, host-specific preferences, and virtual memory files. You can find example files to remove on the asr man page.

7Unmount the volume and convert the read-write image to a read-only compressed image.

hdiutil convert -format UDZO pathtoimage -o compressedimage

8Prepare the image for duplication by adding checksum information:

sudo asr -imagescan compressedimage

To restore a volume from an image:

$ sudo asr -source compressedimage -target targetvolume -erase

See the asr man page for command syntax, limitations, and image preparation instructions.

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Chapter 6 Working With Disks and Volumes

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Apple oxs manual Imaging and Cloning Volumes Using ASR, To image a boot volume, To restore a volume from an image