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NAME

       epmd - Erlang Port Mapper Daemon

DESCRIPTION

       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 epmd 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  Name@Node.  The
       job  of  the epmd daemon is to keep track of which node name listens on
       which  address.  Hence,  epmd  map  symbolic  node  names  to   machine
       addresses.

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

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

EXPORTS

       epmd [-daemon]

              Starts  a  name  server  as a daemon. If it has no argument, the
              epmd 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

              Requests  the  names  of  the  local  Erlang  nodes   epmd   has
              registered.

       epmd -kill

              Kills the epmd process.

       epmd -help

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

ENVIRONMENT VARIABLES

          ERL_EPMD_PORT
             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

             !epmd
             *.*<TABs>/var/log/epmd.log

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