To specify a
destination address to which client messages are forwarded and to enable
Dynamic Host Configuration Protocol (DHCP) for IPv6 relay service on the
interface, use the
command in DHCP IPv6 interface relay configuration mode. To remove a relay
destination on the interface or delete an output interface for a destination,
no form of
destination ipv6 address interface-path-id
no destination ipv6 address
in the form documented in RFC 2373, where the address is specified in
hexadecimal using 16-bit values between colons.
physical interface instance or a virtual interface instance as follows:
Physical interface instance. Naming notation is rack/slot/module/port and a slash between values is required as part of the notation.
rack: Chassis number of the rack.
slot: Physical slot number of the modular services card or line card.
module: Module number. A physical layer interface module (PLIM) is always 0.
port: Physical port number of the interface.
In references to a Management Ethernet interface located on a route processor card, the physical slot number is alphanumeric
(RP0 or RP1) and the module is CPU0. Example: interface MgmtEth0/RP1/CPU0/0.
Virtual interface instance. Number range varies depending on interface type.
information about the syntax for the router, use the question mark (?) online
Relay function is
disabled and there is no relay destination on the interface.
DHCP IPv6 interface relay configuration
for DHCP IPv6 relay service.
command specifies a destination address to which client messages are forwarded
and enables DHCP for IPv6 relay service on the interface. When relay service is
enabled on an interface, a DHCP for IPv6 message received on that interface is
forwarded to all configured relay destinations. The incoming DHCP for IPv6
message may have come from a client on that interface, or it may have been
relayed by another relay agent.
destination can be a unicast address of a server or another relay agent, or it
may be a multicast address. There are the following two types of relay
A link-scoped unicast or multicast IPv6 address, for which a user must specify an output interface
A global unicast IPv6 address, for which a user can specify an output interface for this kind of address.
A global or site-scope multicast IPv6 address, for which a user can specify an output interface for this kind of address if
'mhost ipv6 default-interface' is specified.
If no output
interface is configured for a destination, the output interface is determined
by routing tables. In this case, it is recommended that a unicast or multicast
routing protocol be running on the router.
destinations can be configured on one interface, and multiple output interfaces
can be configured for one destination. When the relay agent relays messages to
a multicast address, it sets the hop limit field in the IPv6 packet header to
loopback, and node-local multicast addresses are not acceptable as the relay
destination. If any one of them is configured, the message "Invalid destination
address" is displayed.
Note that it is not
necessary to enable the relay function on an interface for it to accept and
forward an incoming relay reply message from servers. By default, the relay
function is disabled, and there is no relay destination on an interface. The
no form of the
command removes a relay destination on an interface or deletes an output
interface for a destination. If all relay destinations are removed, the relay
service is disabled on the interface.
The DHCP for IPv6
client, server, and relay functions is mutually exclusive on an interface. When
one of these functions is already enabled and a user tries to configure a
different function on the same interface, one of the following messages is
displayed: “Interface is in DHCP client mode,” “Interface is in DHCP server
mode,” or “Interface is in DHCP relay mode.”
The following is an example of the
command on an interface:
RP/0/RSP0/CPU0:router(config)# dhcp ipv6
RP/0/RSP0/CPU0:router(config-dhcpv6)# interface tenGigE 0/5/0/0 relay
RP/0/RSP0/CPU0:router(config-dhcpv6-if)# destination 10:10::10