--- name: "nmtrapd" section: "8" platform: "linux" package: "scotty" version: "4:00-02-21-2" release: "Debian 3.0 (Woody)" platforms: ["linux"] url: "https://new.carta.tech/nmtrapd" --- # nmtrapd(8) A network management SNMP trap multiplexer. ``` ``` ## NAME nmtrapd - A network management SNMP trap multiplexer. ## SYNOPSIS **nmtrapd** \[ *port* \] ``` ``` ## DESCRIPTION The **nmtrapd** 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 **scotty**). The optional *port* 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 **nmtrapd** daemon must be installed setuid root since UNIX systems require root permissions to open the standard SNMP trap port 162/udp. The **nmtrapd** daemon rejects all *port* numbers below 1024 with the exception of port 162/udp in order to protect the system security. Clients connect to the **nmtrapd** daemon by opening the AF\_UNIX domain stream socket /tmp/.nmtrapd-*port*. Thus, the default AF\_UNIX domain stream socket is named /tmp/.nmtrapd-162. ## PROTOCOL Received messages are forwarded using the following packet format: ``` 0 7 8 15 16 23 24 32 +--------+--------+--------+--------+ | version| unused | port number | +--------+--------+--------+--------+ | IPv4 address of the sender | +--------+--------+--------+--------+ | length of the trap message | +--------+--------+--------+--------+ | trap message | : : : : : +--------+--------+--------+--------+ ``` 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. ## SEE ALSO [scotty(1)](/scotty/1.md), [tkined(1)](/tkined/1.md), Tnm(n) ## AUTHORS Erik Schoenfelder \\ Juergen Schoenwaelder \\