Obtaining debug output for NIM BOS installations

Due to problems in the network or in the NIM configuration, clients may fail to boot or install properly. When this happens, it may be necessary to obtain debug information in order to determine the cause of the problem.

If a client machine fails to configure properly from the network boot image, debug output from the boot image can be obtained by building the debug-enabled image and attaching a tty to the client system. This will display the commands and output that are run while the client is configured before further processing is done by AIX®.

If the system has been booted from the network boot image, but failures are still occurring during a BOS installation, it may be necessary to collect debug information from the BOS installation program. The commands and output from the BOS installation program will automatically be displayed on the tty if the boot image was built debug-enabled. If the boot image was not built for debugging, output can be obtained by either setting a value in a bosinst.data file or by entering special codes at the installation menus.

When problems arise during a NIM BOS installation, you will most likely get system hangs. Viewing the debug output can be useful, because you will be able to see the commands that failed. The problem may be a misconfiguration of the network adapter or an inability to perform an operation from the client to the server. By examining the debug output, you can determine what failed and make corrections to avoid the error in the future.

You will see the showled command running in the debug output. This command displays status values on the LEDs on the front of the machine. Frequently, known problems and solutions are referenced by the LED value that is displayed when a problem occurs. Some machines do not have LEDs for displaying such information. Therefore, when debugging problems on such machines, give special attention to observing the values that the showled commands are displaying.

Obtaining debug information from a network installation can save you time in determining the root cause of a problem. Usually, the problem will be an incorrect definition in the NIM environment that can be found without the debug information. However, with the debug information, you can significantly reduce the scope of the investigation.