This chapter is the starting point for installing and using the Cisco Network Boot product. The chapter provides some very basic information to help you understand its operation. It contains the following topics:
•Basic Network Structure
•Boot Sequence Overview
Cisco Network Boot is a product that allows you to initiate a boot of Windows 2000 Server or Advanced Server on a computer without an attached disk drive.
With Cisco Network Boot, a computer without a directly attached disk drive uses iSCSI protocol via an iSCSI driver to boot from an iSCSI disk through an IP network and a Cisco SN 5400 Series system (see Figure 1-1). As with any iSCSI disk, even though it is not directly attached to the computer accessing it, the disk appears to the computer as if it were directly attached.
Note The iSCSI protocol is an IETF-defined protocol for IP storage (ips). For more information about the iSCSI protocol, refer to the IETF standards for IP storage at http://www.ietf.org.
Figure 1-1 Cisco Network Boot Overview
The Cisco Network Boot product package is a zip program, called netboot-2.1.1.zip, which consists of two components:
•inbp.com—A file downloaded via TFTP by the IP host that initiates a boot. The Cisco Network Boot runs as a Network Bootstrap Program (NBP) in the Preboot Execution Environment (PXE).
•setup.exe—A file that sets up the Network Boot Administration utility. You use the Network Boot Administration utility when you replicate a boot image.
Note The Preboot Execution Environment (PXE) is part of a set of industry-standard specifications that defines a uniform set of preboot services for network-based booting. For more information about PXE, refer to the Wired for Management (WfM) specifications at http://www.intel.com/design/archives/wfm/.
Basic Network Structure
To use Cisco Network Boot, you will need a network that consists of the following elements:
•IP hosts with network interface cards (NICs) that have PXE capability
•Cisco SN 5400 Series system
•Storage attached to a Cisco SN 5400 Series system
•Storage directly attached to one of the IP hosts (master boot host)
Figure 1-2 shows the structure of a basic network that employs Cisco Network Boot. Table 1-1 describes each element.
Figure 1-2 Basic Network Structure
Table 1-1 Basic Network Components
Each host uses Cisco Network Boot to boot from an iSCSI target in a Cisco SN 5400 Series system. Each IP host requires an iSCSI target with a boot image for that host.
Cisco SN 5400 Series system
The Cisco SN 5400 Series system provides iSCSI targets for IP hosts.
A host that provides both a DHCP server and a TFTP server is required for the IP hosts to boot using Cisco Network Boot.
Storage attached to the Cisco SN 5400 Series system
Provides physical storage that IP hosts access through the Cisco SN 5400 Series system.
Storage directly attached to one IP host
A disk drive that is directly attached to an IP host is required to create a master boot image. A master boot image is required for replicating a boot drive image for each IP host.
Note The disk that is directly attached to a host is required only to create a master boot image. Once the master boot image is created, the host no longer needs that disk to boot.
To use the Cisco Network Boot, you will need to perform the following configuration tasks:
•LAN configuration—Make the network connections and configure the Cisco switches.
•Configure a Cisco SN 5400 Series system—Specify iSCSI targets for the hosts.
•Configure a DHCP/TFTP server—For each host, specify parameters for booting over a network.
•Create a master boot image—Install Microsoft Windows 2000 Server or Advanced Server, Cisco iSCSI drivers, and applications on a directly attached disk on the master boot host from which the master boot image can be replicated.
•Replicate the master boot image and other boot images—Replicate the master boot image on the master boot host and other boot images for each host, based on a master boot image. One iSCSI target is required for each replicated boot image. In addition, an iSCSI target may be used to save the master boot image, allowing the directly attached disk to then be removed.
•Configure the IP hosts to boot from the network.
Boot Sequence Overview
After the configuration tasks have been completed, an IP host can boot using Cisco Network Boot. The following steps describe the boot sequence a computer would follow using the Cisco Network Boot:
Step 1 The host requests boot information from the DHCP server.
Step 2 The DHCP server returns boot information, which includes:
•IP address that the host should use
•IP address of the TFTP server
•File name of Cisco Network Boot (inbp.com)
Step 3 The host downloads the inbp.com file from the TFTP server.
Step 4 The host runs the inbp.com file. The inbp.com file boots the host from a boot image that is accessed through the iSCSI target for that host.
Step 5 The operating system starts and the computer is ready to run its applications.