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in.dhcpd(1M)		System Administration Commands		  in.dhcpd(1M)

NAME
       in.dhcpd	- Dynamic Host Configuration Protocol server

SYNOPSIS
       /usr/lib/inet/in.dhcpd  [-denv] [-h relay_hops] [-i interface, ...] [-l
       syslog_local_facility] [-b automatic | manual] [-o DHCP_offer_time] [-t
       dhcptab_rescan_interval]

       /usr/lib/inet/in.dhcpd  [-dv]  [-h  relay_hops]	[-i interface,...] [-l
       syslog_local_facility] -r IP_address | hostname,	...

DESCRIPTION
       in.dhcpd	is a daemon that responds to Dynamic Host Configuration	Proto-
       col (DHCP) requests and optionally to BOOTP protocol requests. The dae-
       mon forks a copy	of itself that runs as a background process.  It  must
       be  run	as  root.  The daemon has two run modes, DHCP server (with op-
       tional BOOTP compatibility mode)	and BOOTP relay	agent mode.

       The first line in the SYNOPSIS section illustrates the  options	avail-
       able  in	 the  DHCP/BOOTP  server mode. The second line in the SYNOPSIS
       section illustrates the options available when the  daemon  is  run  in
       BOOTP relay agent mode.

       The  DHCP and BOOTP protocols are used to provide configuration parame-
       ters to Internet	hosts. Client machines	are  allocated	their  IP  ad-
       dresses	as  well  as  other host configuration parameters through this
       mechanism.

       The DHCP/BOOTP daemon manages  two  types  of  DHCP  data  tables:  the
       dhcptab configuration table and the DHCP	network	tables.

       See  dhcptab(4) regarding the dhcptab configuration table and dhcp_net-
       work(4) regarding the DHCP network tables.

       The dhcptab contains macro definitions  defined	using  a  termcap-like
       syntax  which  permits  network administrators to define	groups of DHCP
       configuration  parameters  to  be  returned  to	clients.  However,   a
       DHCP/BOOTP  server  always returns hostname, network broadcast address,
       network subnet mask, and	IP maximum transfer unit (MTU) if requested by
       a  client  attached to the same network as the server machine. If those
       options have not	been explicitly	configured in  the  dhcptab,  in.dhcpd
       returns reasonable default values.

       The dhcptab is read at startup, upon receipt of a SIGHUP	signal,	or pe-
       riodically as specified by the -t option. A SIGHUP (sent	using the com-
       mand  pkill  -HUP  in.dhcpd) causes the DHCP/BOOTP daemon to reread the
       dhcptab within an interval from 0-60 seconds (depending	on  where  the
       DHCP  daemon  is	 in its	polling	cycle).	For busy servers, users	should
       run /etc/init.d/dhcp stop, followed by /etc/init.d/dhcp start to	 force
       the dhcptab to be reread.

       The  DHCP  network  tables contain mappings of client identifiers to IP
       addresses. These	tables are named after the network  they  support  and
       the datastore used to maintain them.

       The  DHCP network tables	are consulted during runtime. A	client request
       received	from a network for which no DHCP network table exists  is  ig-
       nored.

       This  command  may  change  in  future  releases	 of  Solaris software.
       Scripts,	programs, or procedures	that use this command might need modi-
       fication	when upgrading to future Solaris software releases.The command
       line options provided with the in.dhcpd daemon are used	only  for  the
       current	session,  and  include only some of the	server options you can
       set. The	dhcpsvc.conf(4)	contains all the server	default	settings,  and
       can  be	modified by using the dhcpmgr utility. See dhcpsvc.conf(4) for
       more details.

OPTIONS
       The following options are supported:

       -b  automatic | manual
	     This option enables BOOTP compatibility mode, allowing  the  DHCP
	     server  to	 respond to BOOTP clients.  The	option argument	speci-
	     fies whether the DHCP server should automatically allocate	perma-
	     nent  lease  IP  addresses	 to  requesting	 BOOTP	clients	if the
	     clients are not registered	in the DHCP network tables (automatic)
	     or	 respond  only	to BOOTP clients who have been manually	regis-
	     tered in the DHCP network tables (	manual). This option only  af-
	     fects DHCP	server mode.

       -d    Debugging	mode.  The daemon remains as a foreground process, and
	     displays verbose messages as it processes DHCP and/or BOOTP data-
	     grams.  Messages  are  displayed on the current TTY.  This	option
	     can be used in both DHCP/BOOTP server mode	and BOOTP relay	 agent
	     mode.

       -h relay_hops
	     Specifies	the  maximum number of relay agent hops	that can occur
	     before the	daemon drops the DHCP/BOOTP datagram. The default num-
	     ber of relay agent	hops is	4. This	option affects both DHCP/BOOTP
	     server mode and BOOTP relay agent mode.

       -i interface, ...
	     Selects the network interfaces that the daemon should monitor for
	     DHCP/BOOTP	 datagrams. The	daemon ignores DHCP/BOOTP datagrams on
	     network interfaces	not specified in this  list.  This  option  is
	     only useful on machines that have multiple	network	interfaces. If
	     this option  is  not  specified,  then  the  daemon  listens  for
	     DHCP/BOOTP	 datagrams on all network interfaces. The option argu-
	     ment consists of a	comma-separated	list of	 interface  names.  It
	     affects both DHCP/BOOTP server and	BOOTP relay agent run modes.

       -l syslog_local_facility
	     The presence of this option turns on  transaction logging for the
	     DHCP server or BOOTP relay	agent. The value specifies the	syslog
	     local facility (an	integer	from 0 to 7 inclusive) the DHCP	daemon
	     should use	for tagging the	transactions. Using a  facility	 sepa-
	     rate  from	the LOG_DAEMON facility	allows the network administra-
	     tor to capture these transactions separately from other DHCP dae-
	     mon  events  for such purposes as generating transaction reports.
	     See syslog(3C), for details about local facilities.  Transactions
	     are  logged  using	a record with 9	space-separated	fields as fol-
	     lows:

	     1.	Protocol:

		  Relay	mode:	  "BOOTP"
		  Server mode:	  "BOOTP" or "DHCP" based upon client
				       type.

	     2.	Type:

		Relay mode:	"RELAY-CLNT", "RELAY-SRVR"
		Server mode:	"ASSIGN", "EXTEND", "RELEASE",
				    "DECLINE", "INFORM", "NAK" "ICMP-ECHO."

	     3.	Transaction time: absolute time	in seconds (unix time)

	     4.	Lease time:

		Relay mode:	Always 0.
		Server mode:	0 for ICMP-ECHO	events,	absolute time in
				    seconds (unix time)	 otherwise

	     5.	Source IP address: Dotted Internet form

		Relay mode:	Relay interface	IP on RELAY-CLNT,
				       INADDR_ANY on RELAY-SRVR.
		Server mode:	Client IP.

	     6.	Destination IP address:	Dotted Internet	form

		Relay mode:	Client IP on RELAY-CLNT, Server	IP on
							  RELAY-SRVR.
		Server mode:	Server IP.

	     7.	Client Identifier: Hex representation (0-9, A-F)

		Relay mode:	MAC address
		Server mode:	BOOTP -	MAC address; DHCP - client id

	     8.	Vendor	 Class	 identifier   (white   space   converted    to
		periods	(.)).

		Relay mode:	Always "N/A"
		Server mode:	Vendor class ID	tokenized by
				       converting white	space characters
				       to periods (.)

	     9.	MAC address: Hex representation	(0-9, A-F)

		Relay mode:	MAC address
		Server mode:	MAC address

       The format of this record is subject to change between releases.

       Transactions are	logged to the console if daemon	is in debug mode (-d).

       Logging transactions impact daemon performance.

	     It	 is suggested that you manage log file size periodically using
	     a script run by cron(1M) and sending syslogd(1M) a	SIGHUP signal.
	     You  could, for example, clone /usr/lib/newsyslog and alter it to
	     match your	DHCP logging requirements.

       -n    Disable automatic duplicate IP address detection. When  this  op-
	     tion  is  specified,  the	DHCP server does not attempt to	verify
	     that an IP	address	it is about to offer a client is not  in  use.
	     By	 default,  the DHCP server pings an IP address before offering
	     it	to a DHCP/BOOTP	client,	to verify that the address is  not  in
	     use by another machine.

       -o DHCP_offer_time
	     Specifies	the number of seconds the DHCP server should cache the
	     offers it has extended to discovering DHCP	clients.  The  default
	     setting  is  10 seconds. On slow network media, this value	can be
	     increased to compensate for slow network performance. This	option
	     affects only DHCP server mode.

       -r IP_address | hostname, ...
	     This  option  enables BOOTP relay agent mode. The option argument
	     specifies a comma-separated list of IP addresses or hostnames  of
	     DHCP  or  BOOTP  servers  to  which the relay agent is to forward
	     BOOTP requests. When the daemon is	started	in this	mode, any DHCP
	     tables  are  ignored, and the daemon simply acts as a BOOTP relay
	     agent.

	     A BOOTP relay agent listens to UDP	port 68,  and  forwards	 BOOTP
	     request  packets received on this port to the destinations	speci-
	     fied on the command line. It  supports  the  BROADCAST  flag  de-
	     scribed  in  RFC 1542. A BOOTP relay agent	can run	on any machine
	     that has knowledge	of local routers, and thus does	not have to be
	     an	Internet gateway machine.

	     Note  that	 the proper entries must be made to the	netmasks data-
	     base so that the DHCP server being	 served	 by  the  BOOTP	 relay
	     agents  can  identify  the	 subnet	mask of	the foreign BOOTP/DHCP
	     client's network. See netmasks(4) for the format and use of  this
	     database.

       -t dhcptab_rescan_interval
	     Specifies the interval in minutes that the	DHCP server should use
	     to	schedule the automatic rereading of the	 dhcptab  information.
	     Typically,	 you  would  use  this	option	if  the	changes	to the
	     dhcptab are relatively frequent. Once the contents	of the dhcptab
	     have  stabilized,	you can	turn off this option to	avoid needless
	     reinitialization of the server.

       -v    Verbose mode. The daemon displays more messages than in  the  de-
	     fault  mode.  Note	that verbose mode can reduce daemon efficiency
	     due to the	time taken to display messages.	Messages are displayed
	     to	 the  current  TTY if the debugging option is used; otherwise,
	     messages are logged to the	syslogd	facility. This option  can  be
	     used in both DHCP/BOOTP server mode and BOOTP relay agent mode.

EXAMPLES
       Example 1: Starting a DHCP Server in BOOTP Compatibility	Mode

       The following command starts a DHCP server in BOOTP compatibility mode,
       permitting the server to	automatically allocate permanent IP  addresses
       to BOOTP	clients	which are not registered in the	server's table;	limits
       the server's attention to incoming datagrams on network devices le2 and
       tr0; drops BOOTP	packets	whose hop count	exceeds	2; configures the DHCP
       server to cache extended	DHCP offers  for  15  seconds;	and  schedules
       dhcptab rescans to occur	every 10 minutes:

       # in.dhcpd -i le2,tr0 -h	2 -o 15	-t 10 -b automatic

       Example 2: Starting the Daemon in BOOTP Relay Agent Mode

       The following command starts the	daemon in BOOTP	relay agent mode, reg-
       istering	the hosts bladerunner and 10.0.0.5 as relay destinations, with
       debugging  and verbose modes enabled, and drops BOOTP packets whose hop
       count exceeds 5:

       # in.dhcpd -d -v	-h 5 -r	bladerunner,10.0.0.5

FILES
       /etc/inet/dhcpsvc.conf

       /etc/init.d/dhcp

       /etc/init/hosts

       /usr/lib/inet/dhcp/nsu/rfc2136.so.1

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

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWdhcsu			   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       cron(1M), dhcpmgr(1M), dhtadm(1M), pntadm(1M), syslogd(1M), syslog(3C),
       dhcpsvc.conf(4),	dhcp_network(4), dhcptab(4), ethers(4),	hosts(4), net-
       masks(4), nsswitch.conf(4), attributes(5), dhcp(5)

       System Administration Guide: IP Services

       Alexander, S., and R. Droms, DHCP Options and BOOTP Vendor  Extensions,
       RFC 2132, Silicon Graphics, Inc., Bucknell University, March 1997.

       Droms,  R.,  Interoperation  Between DHCP and BOOTP, RFC	1534, Bucknell
       University, October 1993.

       Droms, R., Dynamic Host Configuration Protocol, RFC 2131, Bucknell Uni-
       versity,	March 1997.

       Wimer,  W.,  Clarifications  and	Extensions for the Bootstrap Protocol,
       RFC 1542, Carnegie Mellon University, October 1993.

SunOS 5.9			  13 Mar 2001			  in.dhcpd(1M)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | FILES | ATTRIBUTES | SEE ALSO

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