Sun Diskless Workstation Boot Sequence

Sun diskless workstations need help in booting. To do this they first need to determine who they are, locate their boot server, locate their kernel and mount file systems.

The following steps outline the client-server boot exchange with a more descriptive process below:

1 C
rarp request to get IP server →→S
2 ←← pass IP back
3 use tfp to get boot program →→
4 ←← send boot program
5 send whoami →→
6 ←← send hostname
7 getfile request for parameters →→
8 ←← pass info in /etc/bootparams
9 boot program NFS mount /vmunix →→
10 ←← client boots and NFS mounts file systems
1 Boot PROM sends reverse address request packet (rarp) onto the network with its Ethernet address to find out who knows its Internet (IP) address (/etc/ethers: ethernet<=>hostname)
2 Server running reverse address resolution protocol daemon (/usr/etc/rarpd) answers with the IP address of the client (/etc/hosts: IP<=>hostname).
3 Client PROM uses trivial file transfer program (tftp) to load the boot program.
4 Server sends the boot program to the client.
5 Boot program issues whoami request to get the clients hostname.
6 Server looks up hostname from IP address and responds to the client (/etc/hosts).
7 Boot program issues a getfile request to determine boot parameters (/etc/bootparams: client root and swap locations).
8 Server running the boot parameter daemon (/usr/etc/rpc.bootparamd) responds with /etc/bootparams information.
9 Boot program NFS mounts the root file system, loads the kernel (/vmunix, for SunOS 4.X), and transfers control to the kernel.
10 The client proceeds to boot normally and NFS mounts other file systems.