JavaStation Client Software Guide

Task 2: Deliver and Boot the JavaOS Software

Task 2 is to pass control of the JavaStation to the JavaOS software. If the JavaOS image has not been loaded from flash memory, it must now be downloaded from the network. The information required for the download was passed to the JavaStation computer in the initial DHCP handshake. Specifically, this information consists of:

The name of the boot protocol to be used for the download (NFS or TFTP)

The IP address of the server where the initial boot file (a "booter" or JavaOS itself) resides

The following table shows JavaOS boot information from the DHCP server and the resulting actions taken by the PROM.

Table 2-1 DHCP Information for Booting JavaOS


If the boot protocol is...	And the DHCP server also delivers...	The JavaOS software is downloaded and booted as follows
Not set or TFTP	The IP address of a server that contains an initial boot program (the "booter") in its TFTP root directory	The JavaStation PROM downloads the booter from the server using TFTP, then transfers control to it. When the booter begins execution, it checks the PROM's device tree for the name and location of the JavaOS image and the name of a server that contains this image in an NFS-exported directory. If the booter does not find this information in the PROM, it obtains it from the DHCP server. The booter mounts this directory using NFS, copies the JavaOS image, and transfers control to it. Note that this method of delivery is deprecated in favor of downloading JavaOS directly over NFS.
	The IP address of a server that contains the JavaOS image in its TFTP root directory	The JavaStation PROM downloads JavaOS from the server using TFTP, then transfers control to it. Note that this method of delivery is much slower than downloading JavaOS over NFS.
NFS	The IP address of a server that contains the JavaOS image in an exported NFS directory	The JavaStation PROM downloads JavaOS from the server using NFS, then transfers control to it.

The DHCP options used to deliver the above information are described in "The DHCP Service Configuration Table ".