Chapter 41WAN Boot (Overview)
This chapter provides an overview of the WAN boot installation method. This chapter describes the following topics.
What Is WAN Boot?
The WAN boot installation method enables you to boot and install software over a wide area network (WAN) by using HTTP. By using WAN boot, you can install the Solaris operating environment on SPARC based systems over a large public network where the network infrastructure might be untrustworthy. You can use WAN boot with security features to protect data confidentiality and installation image integrity.
The WAN boot installation method enables you to transmit an encrypted Solaris Flash archive over a public network to a remote SPARC based client. The WAN boot programs then install the client system by performing a custom JumpStart installation. To protect the integrity of the installation, you can use private keys to authenticate and encrypt data. You can also transmit your installation data and files over a secure HTTP connection by configuring your systems to use digital certificates.
To perform a WAN boot installation, you install a SPARC based system by downloading the following information from a web server over a HTTP or secure HTTP connection.
wanboot program - The wanboot program is the second level boot program that loads the WAN boot miniroot, client configuration files, and installation files. The wanboot program performs tasks similar to those that are performed by the ufsboot or inetboot second level boot programs.
WAN boot file system - WAN boot uses several different files to configure the client and retrieve data to install the client system. These files are located in the /etc/netboot directory of the web server. The wanboot-cgi program transmits thes files to the client as a file system, called the WAN boot file system.
WAN boot miniroot - The WAN boot miniroot is a version of the Solaris miniroot that has been modified to perform a WAN boot installation. The WAN boot miniroot, like the Solaris miniroot, contains a kernel and just enough software to install the Solaris environment. The WAN boot miniroot contains a subset of the software in the Solaris miniroot.
Custom JumpStart configuration files - To install the system, WAN boot transmits sysidcfg, rules.ok, and profile files to the client. WAN boot then uses these files to perform a custom JumpStart installation on the client system.
Solaris Flash archive - A Solaris Flash archive is a collection of files that you copy from a master system. You can then use this archive to install a client system. WAN boot uses the custom JumpStart installation method to install a Solaris Flash archive on the client system. After you install an archive on a client system, the system contains the exact configuration of the master system.
You then install the archive on the client by using the custom JumpStart installation method.
You can protect the transfer of the previously listed information by using keys and digital certificates.
For a more detailed description of the sequence of events in a WAN boot installation, see How WAN Boot Works (Overview).
When to Use WAN Boot
The WAN boot installation method enables you to install SPARC based systems that are located in geographically remote areas. You might want to use WAN boot to install remote servers or clients that are accessible only over a public network.
If you want to install systems that are located on your local area network (LAN), the WAN boot installation method might require more configuration and administration than necessary. For information about how to install systems over a LAN, see Chapter 12, Preparing to Install From the Network (Topics).
How WAN Boot Works (Overview)
WAN boot uses a combination of servers, configuration files, Common Gateway Interface (CGI) programs, and installation files to install a remote SPARC based client. This section describes the general sequence of events in a WAN boot installation.
Sequence of Events in a WAN Boot Installation
Figure 41-1 shows the basic sequence of events in a WAN boot installation. In this figure, a SPARC based client retrieves configuration data and installation files from a web server and an install server over a WAN.
Figure 41-1 Sequence of Events in a WAN Boot Installation
 You boot the client in one of the following ways.
Boot from the network by setting network interface variables in the Open Boot PROM (OBP).
Boot from the network with the DHCP option.
Boot from a local CD-ROM.
The client OBP obtains configuration information from one of the following sources.
From boot argument values that are typed at the command line by the user
From the DHCP server, if the network uses DHCP
The client OBP requests the WAN boot second level boot program (wanboot).
The client OBP downloads the wanboot program from the following sources.
From a special web server, called the WAN boot server, by using the Hyper Text Transfer Protocol (HTTP)
From a local CD-ROM (not shown in the figure)
The wanboot program requests the client configuration information from the WAN boot server.
The wanboot program downloads configuration files that are transmitted by the wanboot-cgi program from the WAN boot server. The configuration files are transmitted to the client as the WAN boot file system.
The wanboot program requests the download of the WAN boot miniroot from the WAN boot server.
The wanboot program downloads the WAN boot miniroot from the WAN boot server by using HTTP or secure HTTP.
The wanboot program loads and executes the UNIX kernel from the WAN boot miniroot.
The UNIX kernel locates and mounts the WAN boot file system for use by the Solaris installation program.
The installation program requests the download of a Solaris Flash archive and custom JumpStart files from an install server.
The installation program downloads the archive and custom JumpStart files over an HTTP or HTTPS connection.
The installation program performs a custom JumpStart installation to install the Solaris Flash archive on the client.
| 
Previous