19962009 Ericsson AB. All Rights Reserved. The contents of this file are subject to the Erlang Public License, Version 1.1, (the "License"); you may not use this file except in compliance with the License. You should have received a copy of the Erlang Public License along with this software. If not, it can be retrieved online at http://www.erlang.org/. Software distributed under the License is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for the specific language governing rights and limitations under the License. epmd Claes Wikström 1 98-01-05 A epmd.xml
epmd Erlang Port Mapper Daemon

This daemon acts as a name server on all hosts involved in distributed Erlang computations. When an Erlang node starts, the node has a name and it obtains an address from the host OS kernel. The name and the address are sent to the daemon running on the local host. In a TCP/IP environment, the address consists of the IP address and a port number. The name of the node is an atom on the form of . The job of the daemon is to keep track of which node name listens on which address. Hence, map symbolic node names to machine addresses.

The daemon is started automatically by the Erlang start-up script.

The program can also be used for a variety of other purposes, for example checking the DNS (Domain Name System) configuration of a host.

 epmd [-daemon] Start a name server as a daemon

Starts a name server as a daemon. If it has no argument, the runs as a normal program with the controlling terminal of the shell in which it is started. Normally, it should run as a daemon.

 epmd -names Request the names of the registered Erlang nodes on this host

Requests the names of the local Erlang nodes has registered.

 epmd -kill Kill the process

Kills the process.

 epmd -help List options

Write short info about the usage including some debugging options not listed here.
Environment variables

This environment variable can contain the port number epmd will use. The default port will work fine in most cases. A different port can be specified to allow several instances of epmd, representing independent clusters of nodes, to co-exist on the same host. All nodes in a cluster must use the same epmd port number.
Logging

On some operating systems syslog will be used for error reporting when epmd runs as an daemon. To enable the error logging you have to edit /etc/syslog.conf file and add an entry

/var/log/epmd.log ]]>

where <TABs> are at least one real tab character. Spaces will silently be ignored.