<HTML ><HEAD ><TITLE >The RPC Portmapper </TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK REL="HOME" TITLE="The Linux NIS(YP)/NYS/NIS+ HOWTO" HREF="index.html"><LINK REL="PREVIOUS" TITLE="How it works" HREF="operation.html"><LINK REL="NEXT" TITLE="What do you need to set up NIS? " HREF="setting_nis.html"></HEAD ><BODY CLASS="SECT1" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >The Linux NIS(YP)/NYS/NIS+ HOWTO</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="operation.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="setting_nis.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="PORTMAPPER" ></A >5. The RPC Portmapper </H1 ><P >To run any of the software mentioned below you will need to run the program /sbin/portmap. Some Linux distributions already have the code in the /sbin/init.d/ or /etc/rc.d/ files to start up this daemon. All you have to do is to activate it and reboot your Linux machine. Read your Linux Distribution Documentation how to do this.</P ><P >The RPC portmapper (portmap(8)) is a server that converts RPC program numbers into TCP/IP (or UDP/IP) protocol port numbers. It must be running in order to make RPC calls (which is what the NIS/NIS+ client software does) to RPC servers (like a NIS or NIS+ server) on that machine. When an RPC server is started, it will tell portmap what port number it is listening to, and what RPC program numbers it is prepared to serve. When a client wishes to make an RPC call to a given program number, it will first contact portmap on the server machine to determine the port number where RPC packets should be sent.</P ><P >Since RPC servers could be started by inetd(8), portmap should be running before inetd is started.</P ><P >For secure RPC, the portmapper needs the Time service. Make sure, that the Time service is enabled in /etc/inetd.conf on all hosts: <TABLE BORDER="1" BGCOLOR="#E0E0E0" WIDTH="100%" ><TR ><TD ><FONT COLOR="#000000" ><PRE CLASS="SCREEN" ># # Time service is used for clock syncronization. # time stream tcp nowait root internal time dgram udp wait root internal</PRE ></FONT ></TD ></TR ></TABLE > </P ><P >IMPORTANT: Don't forget to restart inetd after changes on its configuration file !</P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="operation.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="setting_nis.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >How it works</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" > </TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >What do you need to set up NIS? </TD ></TR ></TABLE ></DIV ></BODY ></HTML >