W&T 57630, Руководство пользователя

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18
W&T
Assigning the IP address
2.4 IP assignment via RARP server
UNIX environments especially often use RARP protocol for
centrally assigning IP addresses. Here TCP/IP devices that want
an IP address send RARP requests with your Ethernet address as
a network broadcast.
Activate the RARP server on the UNIX system and enter the
Ethernet address of the Web-IO in the file
/etc/ethers . You must
also enter the IP address of the Web-IO in the file /etc/hosts .
5763x [Model]
EN=00c03d003fa0
OK xxxxxx
Ethernet address
The Web-IO must be located in the same subnet as the RARP
server.
Example
Your Web-IO has the MAC address EN= 00C03D003FA0 (device
sticker). You want to give it the IP address 172.16.232.17 and the
alias name WEBIO_1:
• Entry in the file /etc/hosts :
172.16.232.17 WEBIO_1
• Entry in the file /etc/ethers :
00:C0:3D:00:3F:A0 WEBIO_1
If the Web-IO‘s IP address is 0.0.0.0 (=Factory Default), RARP
broadcasts are cyclically generated in order to obtain a valid
address from any existing RARP daemon.
If the Web-IO already has a valid IP address, an RARP broadcast
is generated following each reset. If a reply follows within 500ms,
the IP address contained therein is accepted. As with assigning via
the serial port, this method also makes it possible to overwrite a
current IP address.