nmtrapd.8

'\"
'\" Copyright (c) 1994-1996 Technical University of Braunschweig.
'\" Copyright (c) 1996-1997 University of Twente.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
.so man.macros
.TH nmtrapd 8 "July 1997" Tnm "Tnm Tcl Extension"
.BS
'\" Note:  do not modify the .SH NAME line immediately below!
.SH NAME
nmtrapd \- A network management SNMP trap multiplexer.
.SH SYNOPSIS
.B nmtrapd
[
.I "port"
]
.BE

.SH DESCRIPTION

The \fBnmtrapd\fR trap daemon listens on the snmp-trap port (usually
port 162/udp) for incoming SNMP trap or inform messages and forwards
them to all connected clients (like \fBscotty\fR). The optional
\fIport\fR argument allows to use the nmtrapd daemon to forward
messages received on a non standard SNMP trap port. Port numbers below
1024 will be rejected with the exception of the snmp-trap port
162/udp.

The \fBnmtrapd\fR daemon must be installed setuid root since UNIX
systems require root permissions to open the standard SNMP trap port
162/udp. The \fBnmtrapd\fR daemon rejects all \fIport\fR numbers below
1024 with the exception of port 162/udp in order to protect the system
security.

Clients connect to the \fBnmtrapd\fR daemon by opening the AF_UNIX
domain stream socket /tmp/.nmtrapd-\fIport\fR. Thus, the default
AF_UNIX domain stream socket is named /tmp/.nmtrapd-162.

.SH PROTOCOL

Received messages are forwarded using the following packet format:

.CS
 0      7 8     15 16    23 24    32
+--------+--------+--------+--------+
| version| unused |   port number   |
+--------+--------+--------+--------+
|     IPv4 address of the sender    |
+--------+--------+--------+--------+
|    length of the trap message     |
+--------+--------+--------+--------+
|            trap message           |
:        :        :        :        :
+--------+--------+--------+--------+
.CE

The value of the version field is 0 and all the unused bits are
set to 0. The port number and the length of the trap message are
returned in network byte order.

.SH SEE ALSO
scotty(1), tkined(1), Tnm(n)

.SH AUTHORS
Erik Schoenfelder <schoenfr@gaertner.de>
.br
Juergen Schoenwaelder <schoenw@ibr.cs.tu-bs.de>
.br