How the Remote Installation Boot Disk Works

This article describes how the Remote Installation Boot disk works.

The Remote Installation Boot disk allows the RIS server to be used by clients that do not have a PXE-enabled network adapter. The boot disk creates a PXE emulator that works on supported PCI network adapters that allow them to connect to the RIS server. Since one disk works for all network adapters, a specific network boot disk is no longer required. The supported network adapters are listed in the utility that creates the boot disk. This utility is named Rbfg.exe and can be found in the network folder: Note RBFG floppy disks only support the adapters that are listed in the adapters list box. All of the adapters in this list are PCI based adapters. Network adapters that are ISA, ISA(pnp) and PCMCIA based are not supported.

This disk can be useful when you need to use RIS to install programs to a laptop. Because we do not support PCMCIA, you can place the system in a docking station and use a RBFG generated boot disk to connect to the server provided the docking station contains a supported PCI network adapter.

The following list contains the supported network adapters.

3Com Network Adapters

• 3c900 (Combo and TP0)3c900B (Combo, FL, TPC, TP0)3c905 (T4 and TX)3c905B (Combo, TX, FX)

AMD Network Adapters

• AMD PCNet and Fast PC Net

Compaq Network Adapters

• Netflex 100 (NetIntelligent II)Netflex 110 (NetIntelligent III)

Digital Equipment Corporation (DEC) Network Adapters

• DE 450DE 500

Hewlett-Packard Network Adapters

• HP Deskdirect 10/100 TX

Intel Corporation Network Adapters

• Intel Pro 10+Intel Pro 100+ (PCI version only, MiniPCI version is not supported)Intel Pro 100B (including the E100 series)

SMC Network Adapters

• SMC 8432SMC 9332SMC 9432

You cannot add additional network adapters to the RIS Boot disk. Microsoft adds additional network adapters over time and makes the updates in the Rbfg.exe tool available through normal distribution channels, such as the Web, Windows Update, and future service pack or feature pack updates.

What about the GUID of the computer? Because all NETPCs ship with a GUID that is unique how does the RBFG boot disk find a GUID?

When a PXE client connects to the server, one of the items that is exchanged before you are presented with a logon screen is the GUID of the computer. The GUID is a 128-bit integer (16 bytes) that has a very low probability of being duplicated. The GUID is stored with the computer account object that is created in Active Directory. Network adapters that do not have a PXE boot ROM do not have a GUID, so the Boot Information Negotiation Layer (BINL) uses the Media Access Control (MAC) address to create a GUID. (The MAC address is a number that is unique on the network at that time.) Therefore, the newly created computer account object is actually associated with the network adapter, not the computer.

If you move the network adapter to another computer, RIS thinks that the new computer is the old computer. The administrator must delete the GUID from the CAO for the old computer. If a user tries to install the new computer using a different computer name, a duplicate GUID warning displays the names of the computers on the network that already have the same GUID. Relationships of GUIDs to CAOs should be 1 to 1.