Using NIM with ATM networks

Special processing is required to install a machine over an ATM network.

Unlike other network adapters, ATM adapters cannot be used to boot a machine. Installing a machine over an ATM network requires special processing. Normally when a machine performs a network boot over a specified adapter, the adapter is configured by IPL-ROM or firmware. Then a boot image is transferred from the boot server to the client using tftp. This boot image performs further configuration and mounts network installation resources before starting the BOS installation.

Because an ATM adapter cannot be configured by IPL-ROM or firmware, a boot image cannot be obtained over the network to perform a BOS installation. The NIM bos_inst operation must copy a boot image to the hard disk of the client before the machine is rebooted. Some Object Data Manager (ODM) information is also saved on the client machine so that when the machine is rebooted, the ATM adapter can be configured properly.

NIM clients may not have the programs installed to support the special processing required for installation over ATM, so the /usr/lib/boot/bin and /usr/lpp/bos.sysmgt/nim/methods directories are mounted at the client from the NIM master. These directories contain the programs that run during the setup performed by the NIM bos_inst operation.

After the initial setup completes, an at job is issued to reboot the machine after one minute has elapsed. When the machine reboots, the boot image that was copied to the hard disk configures the ATM adapter and mounts network installation resources for the BOS installation. The installation then proceeds as normal until the customization phase. During NIM customization, the ATM adapter is not reconfigured with a mktcpip command because the ODM already contains information carried over from before the machine was reinstalled. All other aspects of NIM customization are the same as for non-ATM clients.