Oki OkiLAN 6120e, User Manual

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Section 4 - Appendix B - Application Considerations
OKI OkiLAN 6120e User’s Guide
TCP/IP
Configuration Files
The purpose of RARP is to look up a 32-bit IP address
given a 48-bit network hardware address. The RARP
server (which is usually a UNIX workstation running a
rarpd daemon) performs this function using two
configuration files and one or more daemons. The
configuration files are “/etc/hosts” and “/etc/ethers” and
the daemon is called rarpd. A name can be assigned to
any device on a network and is arbitrary. For the
following examples the name used for the OkiLAN
6120e is OKIPRINTER. Remember that this name is
arbitrary; a customer can assign any name.
/etc/hosts: The “/etc/hosts” file is where each entry
maps a host name to an IP address. An
example entry is shown below.
192.168.42.55 OKIPRINTER
/etc/ethers: The “/etc/ethers” file is where each entry
maps a host name to a network hardware
address. An example entry is shown below.
00:02:16:17:50:A4 OKIPRINTER
The following sequence of events occurs during the
power up of the OkiLAN 6120e using RARP:
1. The OkiLAN 6120e powers up but does not know its
IP address. However, it does know its network
hardware address.
2. It sends out a RARP request message with its
network hardware address. For this example, the
OkiLAN 6120e address is 00:02:16:17:50:A4.
3. The rarpd daemon running on a RARP server (in this
example the RARP server is a UNIX workstation)
sees the RARP request along with the network
hardware address in the “/etc/ethers” file. The rarpd
daemon finds the host name, OKIPRINTER, listed
as the name associated with the network hardware
address.