Provided by: wide-dhcpv6-client_20060114-1ubuntu1_i386 bug


     dhcp6c - DHCPv6 client daemon


     dhcp6c [-c configfile] [-Ddfi] [-p pid-file] interface [interfaces...]


     dhcp6c works as a DHCPv6 client and gets information from DHCPv6 servers
     to configure the specified interface.  Multiple interfaces can be
     specified separated by spaces or tabs, in which case dhcp6c will work on
     all the interfaces simultaneously.

     The command line options are:

     -c configfile
             Use configfile as the configuration file.

     -d      Print debugging messages.

     -D      Even more debugging information is printed.

     -f      Foreground mode (useful when debugging).  Although dhcp6c usually
             prints warning, debugging, or error messages to syslog(8), it
             prints the messages to standard error if this option is

     -i      Info-req mode.  In this mode, stateless DHCPv6 is executed with
             an automatic configuration, and the obtained info is written to
             stdout.  After this output, the program is terminated.  (suits
             for a use in shell-script etc)

     -p pid-file
             Use pid-file to dump the process ID of dhcp6c.

     The program will daemonize itself on invocation unless the -f or -i
     option is specified.

     Upon receipt of the SIGHUP or SIGTERM signals, dhcp6c will remove all
     stateful resources from the system.  In the former case the daemon will
     then reinvoke itself, while it will stop running in the latter case.  In
     either case, dhcp6c will send DHCPv6 Release messages to release
     resources assigned from servers.


                       is the default file that contains pid of the currently
                       running dhcp6c.
     /etc/dhcp6c.conf  is the default configuration file.
                       is the file to store the client’s DUID.

Configuration Script

     When dhcp6c receives a reply message, it will invoke a supplementary
     configuration script specified in the dhcp6c.conf(5) file.  The daemon
     will provide the script with configuration parameters as environment
     variables, which include:

     REASON  The reason why the script is invoked.  As of this writing, the
             value is always "NBI" and thus meaningless.
             A list of available DNS servers, each of which is an IPv6 numeric
             address and is separated by a white space character.
             A list of DNS names, which provides DNS name search path.
             A list of available NTP servers, each of which is an IPv6 numeric
             address and is separated by a white space character.
             A list of available SIP server addresses, each of which is an
             IPv6 numeric address and is separated by a white space character.
             A list of SIP server domain names.

     Note that the daemon does not always provide all the parameters.  It sets
     an environment variable only when the corresponding configuration
     parameter is provided by the DHCPv6 server.


     daemon(3), dhcp6c.conf(5), dhcp6s(8)

     Ralph Droms, Editor, Dynamic Host Configuration Protocol for IPv6
     (DHCPv6), RFC 3315, 2003.


     The dhcp6c command first appeared in WIDE/KAME IPv6 protocol stack kit.


     dhcp6c is incomplete and violates DHCPv6 protocol spec, in several
     aspects.  In particular, temporary address assignment is intentionally

     Some of useful option type values are still not officially assigned.  The
     current implementation uses experimental values, which may cause
     interoperability problems with other implementations.

     Information Refresh Time Option is not recognized in Info-req mode, since
     dhcp6c terminates after it receives a REPLY message.