NAME¶
dhcp6c —
DHCPv6 client daemon
SYNOPSIS¶
dhcp6c |
[-c
configfile]
[-Ddfi]
[-p
pid-file]
[-P
profile] interface
[interfaces...] |
DESCRIPTION¶
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 specified.
- -i
- Info-req mode. In this mode, stateless DHCPv6 is executed
with the folllowing configuration, and the obtained info is written to
stdout. After this output, dhcp6c is terminated. (suits
for a use in shell-script etc).
interface (interface given in the argument) {
information-only;
script (a script which displays the received information to stdout);
};
Since the configuration is internally generated, you cannot provide a
configuration in this mode. If you want to have different actions for the
stateless DHCPv6 information, you should write an appropriate
configuration and invoke dhcp6c without this
option.
- -p
pid-file
- Use pid-file to dump the process ID
of dhcp6c.
- -P
profile
- Use the given profile defined in the
dhcp6c configuration file for
interfaces which do not have a specific
configuration.
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.
FILES¶
- /var/run/dhcp6c.pid
- is the default file that contains pid of the currently
running dhcp6c.
- /etc/wide-dhcpv6/dhcp6c.conf
- is the default configuration file.
- /var/lib/dhcpv6/dhcp6c_duid
- 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.
- new_domain_name_servers
- A list of available DNS servers, each of which is an IPv6
numeric address and is separated by a white space character.
- new_domain_name
- A list of DNS names, which provides DNS name search
path.
- new_ntp_servers
- A list of available NTP servers, each of which is an IPv6
numeric address and is separated by a white space character.
- new_sip_servers
- A list of available SIP server addresses, each of which is
an IPv6 numeric address and is separated by a white space character.
- new_sip_name
- A list of SIP server domain names.
- new_nis_servers
- A list of available NIS server addresses, each of which is
an IPv6 numeric address and is separated by a white space character.
- new_nis_name
- A list of NIS domain names.
- new_nisp_servers
- A list of available NIS+ server addresses, each of which is
an IPv6 numeric address and is separated by a white space character.
- new_nisp_name
- A list of NIS+ domain names.
- new_bcmcs_servers
- A list of available BCMCS server addresses, each of which
is an IPv6 numeric address and is separated by a white space
character.
- new_bcmcs_name
- A list of BCMCS 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.
SEE ALSO¶
daemon(3),
dhcp6c.conf(5),
dhcp6s(8)
Ralph Droms, Editor,
Dynamic Host Configuration Protocol for IPv6
(DHCPv6), RFC 3315,
2003.
HISTORY¶
The
dhcp6c command first appeared in WIDE/KAME IPv6 protocol
stack kit.
BUGS¶
dhcp6c is incomplete and violates DHCPv6 protocol spec, in
several aspects. In particular, temporary address assignment is intentionally
omitted.
Information Refresh Time Option is not recognized in Info-req mode, since
dhcp6c terminates after it receives a REPLY message.