All NeXT workstations can boot over their network interface. A network boot-strap procedure can be started by entering the appropriate ROM monitor command.
Obtaining an IP address and downloading the boot loader
NeXT workstations first try to acquire an IP address using the Internet Bootstrap Protocol (BOOTP) or the Dynamic Host Configuration Protocol (DHCP) in BOOTP-compatible mode. When using BOOTP, the bootpd server uses the ethernet address of the machine to determine its IP address and a bootloader filename. If the BOOTP request is successful, the firmware in the NeXT expects to be able to download a second-stage boot program via the TFTP protocol. It will do this by setting up a TFTP connection to the server that answered the earlier BOOTP request, and asking for the file returned by the BOOTP request. The second-stage boot program then loads the kernel using NFS.
You can find the second-stage boot program in installation/boot in the NetBSD/next68k distribution. This boot program will then load the netbsd kernel.
The firmware command to load over the network is ben. Use the following syntax to boot NetBSD:
Other arguments can be passed to the boot loader by specifying them on the end of the command line.
To make booting over the network the default, use the p command. At the first prompt, enter `en()netbsd' as the boot command. It is also useful to answer yes to "verbose test mode", so that the monitor displays the boot progress. For example:
NeXT>p boot command: sd()? en()netbsd DRAM tests: yes? yes perform power-on system test: yes? yes sound out tests: yes? yes SCSI tests: yes? yes loop until keypress: no? no verbose test mode: no? yes boot extended diagnostics: no? no serial port A is alternate console: no? yes allow any ROM command even if password protected: no? no allow boot from any device even if password protected: no? no allow optical drive #0 eject even if password protected: yes? yes enable parity checking if parity memory is present: no? no