Configuring Ipv6 Neighbor Discovery; Configuring Neighbor Solicitation Messages - Cisco 7604 Configuration Manual

Configuring IPv6 Neighbor Discovery

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To apply the access list to an interface, enter the following command:
Step 2
hostname(config)# access-group access_list_name {in | out} interface if_name
See the
Configuring IPv6 Neighbor Discovery
The IPv6 neighbor discovery process uses ICMPv6 messages and solicited-node multicast addresses to
determine the link-layer address of a neighbor on the same network (local link), verify the reachability
of a neighbor, and keep track of neighboring routers.
This section contains the following topics:
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Configuring Neighbor Solicitation Messages

Neighbor solicitation messages (ICMPv6 Type 135) are sent on the local link by nodes attempting to
discover the link-layer addresses of other nodes on the local link. The neighbor solicitation message is
sent to the solicited-node multicast address.The source address in the neighbor solicitation message is
the IPv6 address of the node sending the neighbor solicitation message. The neighbor solicitation
message also includes the link-layer address of the source node.
After receiving a neighbor solicitation message, the destination node replies by sending a neighbor
advertisement message (ICPMv6 Type 136) on the local link. The source address in the neighbor
advertisement message is the IPv6 address of the node sending the neighbor advertisement message; the
destination address is the IPv6 address of the node that sent the neighbor solicitation message. The data
portion of the neighbor advertisement message includes the link-layer address of the node sending the
neighbor advertisement message.
After the source node receives the neighbor advertisement, the source node and destination node can
communicate.
Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide using ASDM
10-6
protocol—Specifies the traffic being controlled by the access list entry. This can be the name (ip,
tcp, or udp) or number (1-254) of an IP protocol. Alternatively, you can specify a protocol object
group using object-group grp_id.
source and destination—Specifies the source or destination of the traffic. The source or destination
can be an IPv6 prefix, in the format prefix/length, to indicate a range of addresses, the keyword any,
to specify any address, or a specific host designated by host
src_port and dst_port—The source and destination port (or service) argument. Enter an operator (lt
for less than, gt for greater than, eq for equal to, neq for not equal to, or range for an inclusive
range) followed by a space and a port number (or two port numbers separated by a space for the
range keyword).
icmp_type—Specifies the ICMP message type being filtered by the access rule. The value can be a
valid ICMP type number (from 0 to 155) or one of the ICMP type literals as shown in
"Addresses, Protocols, and
object-group id.
"Example 4: IPv6 Configuration Example" section on page B-13
Configuring Neighbor Solicitation Messages, page 10-6
Configuring Router Advertisement Messages, page 10-8
Figure 10-1 shows the neighbor solicitation and response process.
Ports". Alternatively, you can specify an ICMP object group using
Chapter 10 Configuring IPv6
host_ipv6_addr.
Appendix E,
for an example IPv6 access list.
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