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Catalyst 2975 Switch Software Configuration Guide
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Chapter 35 Configuring IPv6 Host Functions
Understanding IPv6
ICMPv6
The Internet Control Message Protocol (ICMP) in IPv6 generates error messages, such as ICMP
destination unreachable messages, to report errors during processing and other diagnostic functions. In
IPv6, ICMP packets are also used in the neighbor discovery protocol and path MTU discovery.
Neighbor Discovery
The switch supports NDP for IPv6, a protocol running on top of ICMPv6, and static neighbor entries for
IPv6 stations that do not support NDP. The IPv6 neighbor discovery process uses ICMP messages and
solicited-node multicast addresses to determine the link-layer address of a neighbor on the same network
(local link), to verify the reachability of the neighbor, and to keep track of neighboring routers.
The switch supports ICMPv6 redirect for routes with mask lengths less than 64 bits. ICMP redirect is
not supported for host routes or for summarized routes with mask lengths greater than 64 bits.
Neighbor discovery throttling ensures that the switch CPU is not unnecessarily burdened while it is in
the process of obtaining the next hop forwarding information to route an IPv6 packet. The switch drops
any additional IPv6 packets whose next hop is the same neighbor that the switch is actively trying to
resolve. This drop avoids further load on the CPU.
IPv6 Stateless Autoconfiguration and Duplicate Address Detection
The switch uses stateless autoconfiguration to manage link, subnet, and site addressing changes, such as
management of host and mobile IP addresses. A host autonomously configures its own link-local
address, and booting nodes send router solicitations to request router advertisements for configuring
interfaces.
For more information about autoconfiguration and duplicate address detection, see the “Implementing
IPv6 Addressing and Basic Connectivity” chapter of
Cisco IOS IPv6 Configuration Library
on
Cisco.com.
IPv6 Applications
The switch has IPv6 support for these applications:
•
Ping, traceroute, Telnet, TFTP, and FTP
•
Secure Shell (SSH) over an IPv6 transport
•
HTTP server access over IPv6 transport
•
DNS resolver for AAAA over IPv4 transport
•
Cisco Discovery Protocol (CDP) support for IPv6 addresses
For more information about managing these applications, see the “Managing Cisco IOS Applications
over IPv6” chapter and the “Implementing IPv6 Addressing and Basic Connectivity” chapter in the
Cisco IOS IPv6 Configuration Library
on Cisco.com.
Dual IPv4 and IPv6 Protocol Stacks
You must use the dual IPv4 and IPv6 template to allocate ternary content addressable memory (TCAM)
usage to both IPv4 and IPv6 protocols.
shows a router forwarding both IPv4 and IPv6 traffic through the same interface, based on
the IP packet and destination addresses.
Содержание 2975 - Catalyst LAN Base Switch
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Страница 40: ...xxxviii Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Preface ...
Страница 62: ...1 22 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 1 Overview Where to Go Next ...
Страница 398: ...13 30 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 13 Configuring VLANs Configuring VMPS ...
Страница 424: ...15 18 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 15 Configuring VTP Monitoring VTP ...
Страница 628: ...26 8 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 26 Configuring UDLD Displaying UDLD Status ...
Страница 660: ...28 8 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 28 Configuring RMON Displaying RMON Status ...
Страница 888: ...38 32 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 38 Troubleshooting Troubleshooting Tables ...