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inetd(1M)		System Administration Commands		     inetd(1M)

       inetd - Internet	services daemon

       inetd [-d] [-s] [-t] [ -r count interval] [configuration-file]

       inetd is	the server process for the Internet standard services. It usu-
       ally starts up at system	boot time. The	configuration-file  lists  the
       services	that inetd is to provide. If no	configuration-file is given on
       the command line, inetd reads the configuration	information  from  the
       /etc/inetd.conf	file.  If  /etc/inetd.conf is not present, inetd reads
       the  configuration  information	from  /etc/inet/inetd.conf.  See   in-
       etd.conf(4) for more information	on the format of this file.

       inetd  listens  for service requests on the TCP or UDP ports associated
       with each of the	services listed	in the configuration file. When	a  re-
       quest  arrives,	inetd  executes	the server program associated with the

       A service can be	configured to  have  "wait"  wait-status,   in	 which
       case, inetd waits for the server	process	to exit	before starting	a sec-
       ond server process. RPC services	can also be started by inetd.

       inetd provides a	number of simple Internet services  internally.	 These
       include	 echo, discard,	chargen	(character generator), daytime (human-
       readable	time), and time	(machine-readable time,	in  the	 form  of  the
       number of seconds since midnight, January 1, 1900).

       inetd reads the configuration-file and the default settings in /etc/de-
       fault/inetd once	when it	starts up and rereads them again  whenever  it
       receives	a hangup signal, SIGHUP. New services can be activated and ex-
       isting services can be deleted or modified by  editing  the  configura-
       tion-file and then sending inetd	a  SIGHUP signal.

       After it	receives the SIGHUP signal, inetd reads	the configuration-file
       and, for	each service listed, attempts to  bind()   to  that  service's
       port.  The  attempt  might fail if another standalone server or	"wait"
       wait-status server started by inetd is already listening	 on  the  same
       port.  Such a server has	to be killed before inetd can bind to the ser-
       vice's port. inetd defers implementing a	newly read configuration for a
       service	whose  port is busy and	periodically attempts to start listen-
       ing, after logging an error on console. The retry interval is currently
       10 minutes.

       If  you want a "wait" wait-status server	that is	started	by inetd to be
       controlled by that daemon following a kill and restart  of  inetd,  you
       must do one of the following:

	  o  Kill the server before restarting inetd.

	  o  Restart  inetd, kill the server, and wait till the	retry interval
	     elapses. After this time, inetd attempts to  restart  the	server
	     upon the next request for service.

       The  /etc/default/inetd	file  contains the following default parameter
       settings. See FILES.

	     Specifies whether incoming	TCP connections	are traced. The	 value
	     ENABLE_CONNECTION_LOGGING=YES  is	equivalent  to the -t command-
	     line option. The default value for	 ENABLE_CONNECTION_LOGGING  is

	     Specifies	the  TCP wrappers facility will	be used	to control ac-
	     cess to TCP services. The value YES enables checking. The default
	     rameter is	turned on, then	all "streams, nowait" services will be
	     automatically wrapped by the TCP wrappers facility. The stability
	     level of the TCP wrappers facility	and its	configuration files is
	     External.	As the TCP wrappers facility is	not controlled by Sun,
	     intrarelease  incompatibilities  are  not	 uncommon.   See   at-

       For  more  information about configuring	TCP wrappers, you can refer to
       the following man pages,	which are delivered  as	 part  of  Solaris  at
       /usr/sfw/man: tcpd(1M), hosts_access(5).

       -d    Runs inetd	in the foreground and enables debugging	output.

       -s    Allows  you  to run inetd ``stand-alone'' outside the Service Ac-
	     cess Facility (SAF). If the -s option is omitted, inetd will  at-
	     tempt  to	contact	 the  service access controller	(SAC) and will
	     exit if SAC is not	already	running.  See sac(1M).

       -t    Instructs inetd to	trace the incoming connections for all of  its
	     TCP  services.   It  does this by logging the client's IP address
	     and TCP port number, along	with the name of  the  service,	 using
	     the  syslog(3C)  facility.	 "Wait"	wait-status services cannot be
	     traced. When tracing is enabled, inetd uses the  syslog  facility
	     code ``daemon'' and ``notice'' priority level. See	FILES.

       -r    Allows  inetd to detect and then suspend ``broken'' wait services
	     servers and connectionless	datagram services servers,  for	 exam-
	     ple,   UDP	 and  RPC/CLTS.	Without	this detection,	a buggy	server
	     that fails	before consuming the service request  is  continuously
	     restarted	and  taxes  system resources too much. The -r flag has
	     the form:

	     -r	 count interval

	     count  and	interval are decimal numbers that represent the	 maxi-
	     mum   count  of invocations per interval of seconds a service can
	     be	started	before the service is considered  ``broken.''

	     After being considered ``broken,''	a server is suspended for  ten
	     minutes. After ten	minutes, inetd again enables service, trusting
	     the server	to operate correctly.

	     If	the -r flag is not specified, inetd considers -r40  60	to  be

	     Lists the services	inetd is to provide.

       inetd does not return an	exit status.

	     Contains default settings.	inetd reads the	configuration-file and
	     the default settings in /etc/default/inetd	once when it starts up
	     and  rereads  them	 again	whenever  it receives a	hangup signal,
	     SIGHUP. You can override some of the settings by command-line op-

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE	TYPE	     |	     ATTRIBUTE VALUE	   |
       |Availability		     |SUNWcsu			   |

       in.ftpd(1M),  in.rexecd(1M),  in.rshd(1M),  in.tftpd(1M), sac(1M), sys-
       log(3C),	inetd.conf(4), attributes(5)

       Postel, Jon. RFC	862: Echo Protocol. Network  Information  Center,  SRI
       International, Menlo Park, CA, May 1983.

       Postel, Jon. RFC	863: Discard Protocol. Network Information Center, SRI
       International, Menlo Park, CA, May 1983.

       Postel, Jon. RFC	864: Character Generator Protocol. Network Information
       Center, SRI International, Menlo	Park, CA, May 1983.

       Postel, Jon. RFC	867: Daytime Protocol. Network Information Center, SRI
       International, Menlo Park, CA, May 1983.

       Postel, Jon, and	Ken Harrenstien. RFC 868: Time Protocol.  Network  In-
       formation Center, SRI International, Menlo Park,	CA, May	1983.

       The  following man pages	are delivered as part of the SUNWtcpd package:
       tcpd(1M), hosts_access(4)

       Do not configure	 udp services as nowait. This can cause	a race	condi-
       tion  where the inetd program selects on	the socket and the server pro-
       gram reads from the socket. Many	server programs	will fork and  perfor-
       mance will be severely compromised.

       If  you kill and	restart	inetd, be aware	that any environment variables
       in your shell are inherited by a	shell for an incoming telnet  session.
       For example, if you have	USER=root in your environment, a user who con-
       nects to	your machine with telnet inherits USER=root.

       For RPC services, inetd listens on all the transports, not only tcp and
       udp, as specified for each service in the inetd.conf(4) file.

SunOS 5.9			  28 Jan 2002			     inetd(1M)


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