User`s manual

NBO - Network Boot Operating System
3-143
3
NBO uses primarily the BOOTP, RARP, and TFTP protocols to load
the boot file. Refer to the DARPA Internet Request for Comments
RFC-951, RFC-903, and RFC-783, respectively, for the description of
these protocols. You may skip the BOOTP phase (address
determination and bootfile selection) by specifying the IP addresses
(server and client) and the boot filename; the booting process
would then start with the TFTP phase (file transfer) of the boot
sequence.
When the IP addresses are 0 they always force a BOOTP/RARP
phase to occur first. If all (client and server) of the IP addresses are
known/specified, the TFTP phase occurs first. If this phase fails in
loading the boot file, the BOOTP/RARP phase is initiated prior to
subsequent TFTP phase. If the filename is not specified, this also
forces a BOOTP/RARP phase to occur first. Note that the defaults
specified by the command always initiates a BOOTP/RARP phase.
In any case the booting (server) IP address is displayed as well as
that of any failing IP address.
Once the IP addresses are obtained from the BOOTP server (or the
configuration parameters, if specified), the IP addresses are
checked to see if the server and the client are resident on the same
network. If they are not, the gateway IP address is used as the
intermediate server to perform the TFTP phase with.
If the server has only RARP capability, you need to specify the
name of the boot file, either by the command line or the
configuration parameters (
refer to the NIOT command).
Prior to the TFTP phase an ARP request is transmitted for the
hardware (Ethernet) address of the server.
At selected times (when prompted or a time-out condition exists),
the booting process can be aborted by pressing the BREAK key on
the console keyboard or by pressing the abort switch on the front
panel.