Creating an Install Image

Install images are similar to boot images in that client computers can remotely boot from these image files if they're made available from a NetBoot server. However, when a client computer starts up from an install image, the user is presented with the Installer utility instead of the login window. At this point, the user experience is similar to booting up from the Mac OS X installer CDs: You step through a few simple windows in the Installer utility, and then the system from the install image is installed on the local computer's hard disk.

You can also create an automated install: In that case, having the client boot and choose an install image begins the process of installation. You never have to carry around an installation CD again.

To create an install image:

1.	Choose /Applications/Server/Network Image Utility (Figure 11.8). Figure 11.8. Choose /Applications/Server/Network Image Utility. The Network Image Utility opens.
2.	Click the New Install button in the Toolbar (Figure 11.9). Figure 11.9. Click the New Install button.
3.	Under the General settings, fill out the Image Name, Image ID, and Description fields, and choose the Default Language (Figure 11.10). Figure 11.10. On the New Install Image General tab, fill out the Image Name, Image ID, and Description fields, and choose the Default Language.
4.	Click the Contents tab (Figure 11.11). Figure 11.11. Click the New Install Image Contents tab. From the Image Source pop-up menu, choose the volume, image file, or system CDs you wish to convert to an install image.
5.	Click the Installation Options tab (Figure 11.12). Figure 11.12. Click the New Install Image Installation Options tab. The options on this tab are discussed in the "Automating Installations" section later in this chapter. Up to this point you haven't created the image, so you can change almost anything before proceeding.
6.	Click the Create button. Continue through any other dialogs and license agreements until the Save dialog box opens.
7.	In the Save dialog box, choose the destination for the install image (Figure 11.13). Figure 11.13. In the Save dialog, choose a destination for the install image. If you're running the Network Image Utility on a server running the NetBoot service, it will automatically choose the NetBoot share point.
8.	Click the Save button to initiate the creation process. Be patient; it may take a while to create the install image. You can click the disclosure triangle in the bottom-left corner of the Network Image Utility to observe the creation process log (Figure 11.14). Figure 11.14. Click the disclosure triangle in the bottom-left corner of the Network Image Utility to see the New Install Image process log.

Tips

• Once install images are created, they take up quite a bit of space. Be sure you have enough free space for your images prior to image creation.

• If you select the "Checksum destination" option on the Installation Options tab, then after the install process completes, the computer will validate the installed files to ensure a complete copy. Checksum is a fancy way of ensuring that the image data maintains its integrity. That is, it makes sure all bits are exactly what they should be. This option increases the amount of time required to complete the installation.

• A Block Copy Install Image uses asr (Apple Software Restore) to speed up the process of installation by doing a block-by-block copy.