DHCP(8)                                                   DHCP(8)

     NAME
          dhcp - configure network interface details using DHCP

     SYNOPSIS
          ip/dhcp [ -bdmpr ] [ -g gateway ] [ -h hostname ] [ -x net ]
          ifcdir [ localip [ localmask ]]

     DESCRIPTION
          Dhcp uses the Dynamic Host Configuration Protocol (DHCP) to
          configure the ip(3) interface represented by ifcdir (eg,
          /net/ipifc/1).  The interface must have a device already
          bound to it.  Dhcp uses the MAC address of that device in
          its requests.

          Dhcp broadcasts a DHCP request for an address and various
          network parameters.  It takes the first acceptable offer,
          sets the interface to that address, and writes the address
          and parameter values, in ndb(6) format, to /net/ndb, where
          cs(8), dns(8) and others will find them.  If the address is
          provided with a limited lease, dhcp itself returns, but it
          leaves a process in the background that periodically renews
          the lease (or requests a new address if the lease is not
          renewed).

          If localip is given, dhcp attempts to reacquire that
          address.  If successful, it configures the interface with
          that address (and mask if supplied), maintaining any lease
          as before.  If it cannot reacquire the address, it broad-
          casts a request for a new address, as above.

          The options are:

          -b   Use plain BOOTP without the DHCP options

          -d   Enable debugging output on standard output

          -g gateway
               Suggest gateway as the default gateway (the server
               might change it)

          -h hostname
               Use hostname as the current host's name in DHCP mes-
               sages

          -m   Monitor the DHCP status and print a summary on standard
               output whenever it changes

          -n   Do not configure the interface

          -p   Print the resulting configuration on standard output

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     DHCP(8)                                                   DHCP(8)

          -r   Retry DHCP periodically until it succeeds

          -x net
               Use mount point net to access the network, and write
               the results to net/ndb (default: /net)

     EXAMPLE
          Allocate a new interface, bind an ether device to it, and
          configure it with dhcp:

               x=`{cat /net/ipifc/clone}
               echo bind ether /net/ether0 >/net/ipifc/$x/ctl &&
               ip/dhcp /net/ipifc/$x

     SOURCE
          /appl/cmd/ip/dhcp.b

     SEE ALSO
          ip(3), ndb(6), cs(8), dns(8)

     DIAGNOSTICS
          Dhcp returns an error status if it receives no acceptable
          reply, unless the -r option is given to force retries.

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