$Id: dhcp6s.conf.5,v 1.1.1.1 2006/12/04 00:45:30 Exp $

Copyright (C) International Business Machines Corp., 2003
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. Neither the name of the project nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.

dhcp6s.conf - configuration file of the DHCPv6 server daemon, dhcp6s dhcp6s.conf contains the configuration information of addresses, prefixes, or various network configuration parameters for each of the interfaces. The network configuration parameters can be described globally for all of the interfaces. The default address preferred life time is 36000 seconds; the default address valid life time is 72000 seconds if they are not defined in any declaration. The specific declaration order is interface, link, host; within link the more specific declaration is pool. The interface definitions are described in the following form:

 \tinterface <interface name>  \t{  \t\t[declarations];  \t}; 

where each of the declarations could be of type link, group, or host. Each declaration and the statements within each of these declarations must be terminated by a semicolon. Additional details of the declarations are specified below.

DECLARATIONS

 interface <interface name>  {  \t[declarations];  }; 

An interface declaration is used to inform the DHCPv6 server that the links and hosts declared within it are connected to the same network segment. Common network parameters for this network segment can be defined within the interface declaration.

 link <link name>  {  \t[declarations];  }; 

A link declaration is used to provide the DHCPv6 server the IPv6 assgined address ranges, prefixes, and hosts. Common network parameters for this link can be defined within the link declaration.

 group  {  \t[declarations];  }; 

A group declaration is used to group a list of declarations together to define the common network parameters. These network parameters are valid within this declaration only. Declarations can be one of the following types: interface, link, pool, or host.

 pool  {  \t[declarations];  }; 

The pool declaration is used to declare an address pool from which IPv6 address can be allocated, with its own permit to control client access and its own declaration in which you can declare pool-specific network parameters.

 host <host name>  {  \t[duid <DUID\n>];  \t[iaidinfo {}];  \t[address {}];  \t[prefix <prefix>/<prefix length>];  \t[declarations];  }; 

This declaration allows administrators to describe the addresses, prefixes, and network configuration parameters for this host. As for this declaration, the DHCP Unique Identifier (DUID), Identity Association Identifier (IAID), and addresses must be specified. The host declaration is used to do Static Address Assginment for a particular DHCPv6 client.

 address  {  \t[<ipv6 address>/<prefix length>];  \t[prefer-life-time <preferred lifetime>];  \t[valid-life-time <valid lifetime>];  }; 

This statement allows administrators to specify the address for the host. Preferred Lifetime and Valid Lifetime also can be set in this statement. This statement is valid only in host {} declarations.

 prefix <prefix>/<prefix length>; 

This statement allows administrators to specify the prefix. This parameter is needed when configuring dhcp6s as the Delegation Router for the Prefix Delegation. dhcp6s assigns the specified prefixes to the requesting routers.

 relay <relay>/<prefix length>; 

This statement specifies the prefix that the relay agent will put in the link address field of the RELAY-FORW message to indicate the link the client is +attached to. If the link-address matches this prefix, this link declaration will be used. This statement is only valid in the link declaration.

 iaidinfo  {  \t[iaid <IAID number>];  \t[renew-time <renew time>];  \t[rebind-time <rebind time>];  }; 

This statement allows administrators to describe the information for this IAID. This statement is only valid in host {} declarations. iaid is required; renew-time and rebind time are optional in this statement.

 range <ipv6 address> to <ipv6 address>/<prefix length>; 

This statement allows adminstrators to use "range" and "to" keywords and prefix length to specify an address range. For each range not more than one of the unassigned addresses will be assgined to the requested client.

 duid <DUID\>; 

DUID is a DHCP Unique Identifier for a DHCP participant. Using this option, the administrator can specify the DUID of this DHCPv6 client. The duid statement is valid only in host {} declarations.

 iaid <IAID number>; 

IAID is a Identity Association Identifier. IA is a collection of addresses assigned to a client. Using this option, the administrator can specify the IAID in iaidinfo for a host declaration.

 renew-time <renew time>; 

This statement allows administrators to specify the RenewTime (T1). The recommended value for RenewTime is .5 times the shortest preferred lifetime of the address in the IA, if the value is not defined.

 rebind-time <rebind time>; 

This statement allows administrators to specify the RebindTime (T2). The recommended value for RenewTime is .8 times the shortest preferred lifetime of the address in the IA, if the value is not defined.

 prefer-life-time <preferred lifetime>; 

This statement allows administrators to specify the Preferred Life Time for each address.

 valid-life-time <valid lifetime>; 

This statement allows administrators to specify the Valid Life Time for each address.

 option dns_server <ipv6 addresses or domain name list>; 

This statement allows administrators to specify the DNS servers. send <OPTION>; This declaration enables dhcp6s to include the specified option in sending DHCPv6 messages.

send unicast;

This declaration enables dhcp6s to send a Server Unicast option. Usually DHCPv6 clients must use multicast addresses to contact the DHCPv6 server and agents. This declaration specifies that dhcp6s will accept unicast messages from DHCPv6 clients if they include a Server Unicast option.

send server-preference <server preference value>;

This declaration enables dhcp6s to include a Preference option for sending DHCPv6 messages. DHCPv6 clients will pick up the DHCPv6 server which has highest preference value. The highest preference value is 255.

send temp-address;

This declaration assigns a temporary address to the requesting client.

send information-only;

This option enables dhcp6s to give only configuration information rather than assigning client addresses. This could be, for example, DNS server address configuration information.

 allow <OPTION>; 

This declaration allows the DHCPv6 client to specify an option in receiving DHCPv6 messages.

allow rapid-commit;

This option enables dhcp6s to allow the Rapid-Commit option from the DHCPv6 client and the Solicit-Reply message exchanges.

allow unicast;

This option enables dhcp6s to allow the Server Unicast option for the DHCPv6 client. Usually DHCPv6 clients must use multicast addresses to contact DHCPv6 server and agents. With this declaration, dhcp6s accepts unicast messages from DHCPv6 clients if they include a Server Unicast option.

This is a sample of the dhcp6s.conf file.

 option dns\_server 2003::6:1 ibm.com;  prefer-life-time 10000;  valid-life-time 20000;  renew-time 5000;  rebind-time 8000;  interface eth1 {  \tlink AAA {  \t\tallow unicast;  \t\tsend unicast;  \t\tallow rapid-commit;  \t\tsend server-preference 5;  \t\trenew-time 1000;  \t\trebind-time 2400;  \t\tprefer-life-time 2000;  \t\tvalid-life-time 3000;  \t\trange 3ffe:ffff:100::10 to 3ffe:ffff:100::110/64;  \t\tprefix 3ffe:ffef:104::/64;  \t\tpool {  \t\t\tprefer-life-time 3600;  \t\t\tvalid-life-time 7200;  \t\t\trange fec0:ffff::10 to fec0:ffff::110/64;  \t\t\tprefix fec0:fffe::/48;  \t\t};  \t};  \thost host0 {  \t\tduid 00:00:00:00:a0:a0;  \t\tiaidinfo {  \t\t\tiaid 101010;  \t\t\trenew-time 1000;  \t\t\trebind-time 2000;  \t\t};  \t\taddress {  \t\t\t3ffe:ffff:102::120/64;  \t\t\tprefer-life-time 2000;  \t\t\tvalid-life-time 3000;  \t\t};  \t};  \tgroup {  \t\tprefer-life-time 5000;  \t\tvalid-life-time 6000;  \t\thost host1 {  \t\t\tduid 00:00:00:00:a1:a1;  \t\t\tiaidinfo {  \t\t\t\tiaid 101011;  \t\t\t\trenew-time 1000;  \t\t\t\trebind-time 2000;  \t\t\t};  \t\t};  \t\thost host2 {  \t\t\tduid 00:00:00:00:a2:a2;  \t\t\tsend information-only;  \t\t};  \t};  }; 

Dynamic Host Configuration Protocol for IPv6 (DHCPv6), IPv6 Prefix Options for DHCPv6, dhcp6s(5)

Kazuo Hiekata <hiekata@yamato.ibm.com>