rarpd - TCP/IP Reverse Address Resolution Protocol server
/usr/etc/rarpd interface [ hostname ]
This program is available with the Networking software installation
option. Refer to for information on how to install optional software.
rarpd starts a daemon that responds to Reverse Address Resolution Pro-
tocol (RARP) requests. The daemon forks a copy of itself that runs in
background. It must be run as root.
RARP is used by machines at boot time to discover their Internet Proto-
col (IP) address. The booting machine provides its Ethernet Address in
an RARP request message. Using the "ethers" and "hosts" databases,
rarpd maps this Ethernet Address into the corresponding IP address
which it returns to the booting machine in an RARP reply message. The
booting machine must be listed in both databases for rarpd to locate
its IP address. rarpd issues no reply when it fails to locate an IP
address. The "ethers" and "hosts" databases may be contained either in
files under /etc or in Network Information Service (NIS) maps.
In the first synopsis, the interface parameter names the network inter-
face upon which rarpd is to listen for requests. The interface parame-
ter takes the "name unit" form used by ifconfig(8C). The second argu-
ment, hostname, is used to obtain the IP address of that interface. An
IP address in "decimal dot" notation may be used for hostname. If
hostname is omitted, the address of the interface will be obtained from
the kernel. When the first form of the command is used, rarpd must be
run separately for each interface on which RARP service is to be sup-
ported. A machine that is a router may invoke rarpd multiple times,
/usr/etc/rarpd ie0 host
/usr/etc/rarpd ie1 host-backbone
In the second synopsis, rarpd locates all of the network interfaces
present on the system and starts a daemon process for each one that
ethers(5), hosts(5), policies(5), boot(8S), ifconfig(8C), ipallocd(8C),
Finlayson, Ross, Timothy Mann, Jeffrey Mogul, and Marvin Theimer, A
Reverse Address Resolution Protocol, RFC 903, Network Information Cen-
ter, SRI International, Menlo Park, Calif., June 1984.
The Network Information Service (NIS) was formerly known as Sun Yellow
Pages (YP). The functionality of the two remains the same; only the
name has changed.
18 December 1989 RARPD(8C)