76 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
.TH RARPD 8
 | 
						|
.SH NAME
 | 
						|
rarpd \- reverse address resolution protocol daemon
 | 
						|
.SH SYNOPSIS
 | 
						|
.B rarpd
 | 
						|
.RB [ \-d [\fIlevel\fR]]
 | 
						|
.I network-name
 | 
						|
\&...
 | 
						|
.SH DESCRIPTION
 | 
						|
.de SP
 | 
						|
.if t .sp 0.4
 | 
						|
.if n .sp
 | 
						|
..
 | 
						|
.B Rarpd
 | 
						|
listens on the given networks for broadcast packets asking for reverse address
 | 
						|
resolution.  These packets are sent by hosts at boot time to find out their
 | 
						|
IP address.
 | 
						|
.B Rarpd
 | 
						|
looks up the six octet ethernet number in the
 | 
						|
.B /etc/ethers
 | 
						|
file finding a host name.  This name is translated to the IP address of the
 | 
						|
host by a DNS lookup.  The IP address is then sent to the host.
 | 
						|
.PP
 | 
						|
Under MINIX 3 the program forks as needed to give each network its own server.
 | 
						|
Under Minix-vmd all networks are handled in the same program using async I/O.
 | 
						|
.SS "Private Ethernet Addresses"
 | 
						|
For VU practical work, where students have to create their own IP stack
 | 
						|
starting at the bottom with RARP, this implementation recognizes Ethernet
 | 
						|
addresses starting with octet 0x76 as special.  The next octet is used as a
 | 
						|
additional host number and the next and last four octets as an IP address
 | 
						|
that this Ethernet address is additional for.  The IP address is translated
 | 
						|
back to a name, and the first component of that name gets a dash and the
 | 
						|
additional host number added to it.  That hostname is then looked up and its
 | 
						|
IP address returned in a RARP reply.  Example:
 | 
						|
.PP
 | 
						|
.RS
 | 
						|
.ta +\w'flotsam-3.example.commmm'u
 | 
						|
76:3:c0:a8:e7:fa	Additional 3, IP 192.168.231.250
 | 
						|
.SP
 | 
						|
flotsam.example.com	Reverse lookup on 192.168.231.250
 | 
						|
.SP
 | 
						|
flotsam-3.example.com	Splicing in additional number
 | 
						|
.SP
 | 
						|
192.168.231.42		Forward lookup
 | 
						|
.RE
 | 
						|
.PP
 | 
						|
In this example a RARP query for 76:3:c0:a8:e7:fa gets 192.168.231.42 as reply.
 | 
						|
.SH OPTIONS
 | 
						|
.TP
 | 
						|
.BR \-d [\fIlevel\fP]
 | 
						|
Turns on debugging messages at the given level, by default 1.  At level 1 you
 | 
						|
will be shown what answers are sent, and at level 2 or higher you will be told
 | 
						|
about queries from unknown hosts or host on the wrong network.
 | 
						|
The debug level can also be increased by 1 at runtime by sending signal
 | 
						|
.B SIGUSR1
 | 
						|
or turned off (set to 0) with
 | 
						|
.BR SIGUSR2 .
 | 
						|
.SH "SEE ALSO"
 | 
						|
.BR ifconfig (8),
 | 
						|
.BR ethers (5),
 | 
						|
.BR hosts (5),
 | 
						|
.BR inet (8),
 | 
						|
.BR boot (8),
 | 
						|
.BR dhcpd (8),
 | 
						|
.BR irdpd (8),
 | 
						|
.BR inetd (8),
 | 
						|
.BR nonamed (8).
 | 
						|
.SH NOTES
 | 
						|
A "network name" is the device name of the IP device of a network, i.e.
 | 
						|
.BR ip0 ,
 | 
						|
.BR ip1 ", ..."
 | 
						|
.PP
 | 
						|
The RARP protocol has gone out of fashion in favour of DHCP.
 | 
						|
.SH AUTHOR
 | 
						|
Kees J. Bot (kjb@cs.vu.nl)
 |