This article tells how to update the NetBoot HD.img to Mac OS 8.6 for use with Mac OS X Server's NetBoot Server and the benefits of doing so.

The Mac OS 8.6 Update should be applied to the NetBoot HD.img with the NetBoot Desktop Admin 1.1 application. Please note that the NetBoot Desktop Admin must be updated to version 1.1. This update is available from:

http://asu.info.apple.com/swupdates.nsf/artnum/n11362

A clean installation of Mac OS 8.6 is not recommended. A clean installation requires the NetBoot HD.img to be resized. Use the update install instead. The Mac OS 8.6 Update install is available from:

http://asu.info.apple.com/swupdates.nsf/artnum/n11386

Changes made to the version of the Mac OS ROM file in Mac OS 8.6 greatly reduce the size of NetBoot "Shadow" files resident on the NetBoot Server from roughly 230 Mbytes to approximately 4 Mbytes. When running the NetBoot Desktop Admin application it is not necessary to manually update the Mac OS ROM file located in the "Shared Images" folder. The NetBoot Desktop Admin application checks for a modified Mac OS ROM in the NetBoot HD.img and update the file in the "Shared Images" folder automatically as necessary. It is necessary to update the NetBoot HD.img to Mac OS 8.6 in order to properly NetBoot PowerBook G3 Series (Bronze keyboard) computers. For more information, please see the following article:

Article 58346: " PowerBook G3 Series (Bronze keyboard): NetBooting With Mac OS 8.5.1 Not Supported. "

Similar more generic instructions than the following are also available from the "About NetBoot Desktop Admin" Read Me that accompanies the NetBoot Desktop Admin application:

Installation Instructions

To install Mac OS 8.6 or other System Software updates to the NetBoot HD disk images, you need to log on to a NetBoot client computer, connnect to the NetBoot server volume, and open the NetBoot Desktop Admin program several times. Your changes are not available to you or other users until after the NetBoot client computer restarts the last time.

Before you start, you need the following information:

• Name and password for a Global Administrator who belongs to the System Access workgroup.
• Name and password of a user with read and write access privileges to the NetBoot server volume (for example, the Administrator of the Mac OS X Server).

2. Open the NetBoot Desktop Admin application and log on to the server volume as a user with read and write access privileges (for example, the Administrator of the Mac OS X Server).

The application is installed originally in the NetBoot Desktop Admin folder, which is in the Admin folder on the NetBoot server.

3. Click Make Private Copy.

NetBoot Desktop Admin creates copies of the disk images which you can change. This may take several minutes and you should not interrupt the process. When it finishes, your NetBoot client computer restarts automatically.

IMPORTANT Because the copies of the disk images are associated with the NetBoot client computer you used to create them, you must make the changes to the images using the same computer. If you change computers, you cannot see the changes you have made and your changes are not available to users. In addition, you increase the risk of unauthorized persons making changes to the disk images.

4. Log on to the NetBoot client computer again as the same user and install the Mac OS 8.6 Update on the NetBoot HD image. The Mac OS 8.6 default installation places newer versions of certain files on the NetBoot HD disk image, but does not remove the older versions which are on the Applications HD disk image. After installing Mac OS 8.6, you need to move the newer versions from the NetBoot HD to the Applications HD, and delete the older versions. It may also be necessary to update any aliases to those items. Certain items such as Apple Secure Compression are not contained within the Apple Extras folder installed by updating to Mac OS 8.6. Extra care should be taken to not overwrite these items when updating the Applications HD image.

5. Be sure there aren't any files in the Trash that you want to save. (The Trash is emptied automatically after the next step.)

Note : If you cannot empty the Trash because it contains files that are in use, you may need to restart the computer and log on to the NetBoot client computer again.

6. Open the NetBoot Desktop Admin application and log on to the server, then click Save or Discard. The computer restarts automatically.

If you need to make other changes, you can click Quit and return to step 4.

7. Log on to the NetBoot client computer again, then open the NetBoot Desktop Admin application and log on to the server.

If you want to keep a backup copy of the old disk image, leave the "Keep previous disks as backup" option selected. Backup copies are stored in the Backup Images folder in the Shared Images folder on the NetBoot server.

8. If you clicked Save in step 6, click Restart. Otherwise, click OK.

If you click Restart, NetBoot Desktop Admin saves your changes, deletes the copies of the disk images, then restarts the computer. Changes are available the next time a NetBoot client computer restarts. If you click OK, NetBoot Desktop Admin deletes the copies of disk images.