Bay Networks 6300 Supplement Manual page 66

Chapter 2 Configuring the Remote Annex 6300 Book A
The Annex uses the RWHO protocol as a name server. The Annex runs
an rwhod that listens for broadcasts from other hosts, but does not
broadcast information about itself. When the Annex receives an RWHO
message, it stores the host name, status information, and the source
address from the IP header as the host's Internet address in its host table.
Using only RWHO messages to build the host table is satisfactory for a
small network in which all the hosts run rwhod. But, rwhod often is not
used in networks primarily comprised of workstations because of the load
it imposes on hosts. In large or heavily loaded networks, RWHO
broadcasts can impose an excessive load on the network.
Some hosts send RWHO packets with incomplete source addresses in the
IP header. The Annex is unable to store an Internet address for these hosts,
causing the host table to display the host's Internet address as "_._._._".
If an rwhod forwards packets from one network to another, the Internet
address in the IP header is that of the forwarding host, not of the host
whose name is in the data packet. This results in the Annex storing the
wrong Internet address for that host.
Because the Annex does not broadcast RWHO messages, Annex names
never appear in host tables built exclusively from these broadcasts. In
which case, the only way to access an Annex using the telnet command
is with an Internet address.
The rwho parameter defines whether or not the Annex listens for RWHO
broadcasts. Setting the parameter to N disables the Annex's rwhod and
prevents the Annex from using RWHO messages for building the host
table. The default is Y.
Remote Annex 6300 Supplement to the Remote Annex Administrator's Guide for UNIX
A-38