Cisco ME 3400E Ethernet Access Switch Software Configuration Guide, Cisco IOS Release 12.2(58)EZ

Configuring IPv6 Unicast Routing

This chapter describes how to configure IPv6 unicast routing on the Cisco ME 3400E Ethernet Access switch. Cisco IOS Release 12.2(58)SE adds support for IPv6 unicast routing in VPN routing and forwarding (VRF) and VRF-aware IPv6 DHCP server /client for switches running the metro IP access image.

For information about configuring IPv4 unicast routing, see Chapter 34 "Configuring IP Unicast Routing." For information on configuring IPv6 access control lists (ACLs) see Chapter 40 "Configuring IPv6 ACLs."

To enable IPv6 routing, you must configure the switch to use the a dual IPv4 and IPv6 switch database management (SDM) template. To configure IPv6 VRF-aware routing, you must use the dual-ipv4-and-ipv6 routing template or the dual-ipv4-and-ipv6 default template. The dual-ipv4-and-ipv6 vlan template does not support VRF-aware routing. See the "Dual IPv4 and IPv6 Protocol Stacks" section.

Note For complete syntax and usage information for the commands used in this chapter, see the Cisco IOS documentation referenced in the procedures.

•"Understanding IPv6" section

•"Configuring IPv6" section

•"Displaying IPv6" section

Understanding IPv6

IPv4 users can move to IPv6 and receive services such as end-to-end security, quality of service (QoS), and globally unique addresses. The IPv6 address space reduces the need for private addresses and Network Address Translation (NAT) processing by border routers at network edges.

For information about IPv6 and other features in this chapter, see these documents.

•For complete syntax and usage information for the commands used in this chapter, see the Cisco IOS IPv6 Command Reference:
http://www.cisco.com/en/US/docs/ios/ipv6/command/reference/ipv6_book.html

•For all IPv6 configuration information, see the Cisco IOS IPv6 Configuration Guide, Release 12.4T
http://www.cisco.com/en/US/docs/ios/ipv6/configuration/guide/12_4t/ipv6_12_4t_book.html

•You can also use the Search field to locate the Cisco IOS software documentation for a specific topic. For example, if you want information about static routes, you can enter Implementing Static Routes for IPv6 in the search field to get this document about static routes:

http://www.cisco.com/en/US/docs/ios-xml/ios/ipv6/configuration/12-4t/ip6-stat-routes.html

This section describes IPv6 implementation on the switch. These sections are included:

•IPv6 Addresses

•Supported IPv6 Unicast Routing Features

•Unsupported IPv6 Unicast Routing Features

•Limitations

IPv6 Addresses

The switch supports only IPv6 unicast addresses. It does not support site-local unicast addresses, anycast addresses, or multicast addresses.

The IPv6 128-bit addresses are represented as a series of eight 16-bit hexadecimal fields separated by colons in the format: n:n:n:n:n:n:n:n. This is an example of an IPv6 address:

2031:0000:130F:0000:0000:09C0:080F:130B

For easier implementation, leading zeros in each field are optional. This is the same address without leading zeros:

2031:0:130F:0:0:9C0:80F:130B

You can also use two colons (::) to represent successive hexadecimal fields of zeros, but you can use this short version only once in each address:

2031:0:130F::09C0:080F:130B

For more information about IPv6 address formats, address types, and the IPv6 packet header, see the "Implementing IPv6 Addressing and Basic Connectivity" chapter of Cisco IOS IPv6 Configuration Library on Cisco.com.

In the "Information About Implementing Basic Connectivity for IPv6" chapter, these sections apply to the switch:

•IPv6 Address Formats

•IPv6 Address Type: Unicast

•IPv6 Address Output Display

•Simplified IPv6 Packet Header

Supported IPv6 Unicast Routing Features

Support on the switch includes expanded address capability, header format simplification, improved support of extensions and options, and hardware parsing of the extension header. The switch supports hop-by-hop extension header packets, which are routed or bridged in software.

The switch provides IPv6 routing capability over 802.1Q trunk ports for static routes, Routing Information Protocol (RIP) for IPv6, and Open Shortest Path First (OSPF) Version 3 Protocol. It supports up to 16 equal-cost routes and can simultaneously forward IPv4 and IPv6 frames at line rate.

•128-Bit Unicast Addresses

•DNS for IPv6

•Path MTU Discovery for IPv6 Unicast

•ICMPv6

•Neighbor Discovery

•Default Router Preference

•IPv6 Stateless Autoconfiguration and Duplicate Address Detection

•IPv6 Applications

•Dual IPv4 and IPv6 Protocol Stacks

•DHCP for IPv6 Address Assignment

•DHCP for IPv6 Server, Client, and Relay

•Static Routes for IPv6

•RIP for IPv6

•OSPF for IPv6

•EIGRP IPv6

•Multiprotocol BGP for IPv6

•SNMP and Syslog Over IPv6

•HTTP(S) Over IPv6

•Multiprotocol BGP for IPv6

128-Bit Unicast Addresses

The switch supports aggregatable global unicast addresses and link-local unicast addresses. It does not support site-local unicast addresses.

•Aggregatable global unicast addresses are IPv6 addresses from the aggregatable global unicast prefix. The address structure enables strict aggregation of routing prefixes and limits the number of routing table entries in the global routing table. These addresses are used on links that are aggregated through organizations and eventually to the Internet service provider.

These addresses are defined by a global routing prefix, a subnet ID, and an interface ID. Current global unicast address allocation uses the range of addresses that start with binary value 001 (2000::/3). Addresses with a prefix of 2000::/3(001) through E000::/3(111) must have 64-bit interface identifiers in the extended unique identifier (EUI)-64 format.

•Link local unicast addresses can be automatically configured on any interface by using the link-local prefix FE80::/10(1111 1110 10) and the interface identifier in the modified EUI format. Link-local addresses are used in the neighbor discovery protocol (NDP) and the stateless autoconfiguration process. Nodes on a local link use link-local addresses and do not require globally unique addresses to communicate. IPv6 routers do not forward packets with link-local source or destination addresses to other links.

For more information, see the section about IPv6 unicast addresses in the "Implementing IPv6 Addressing and Basic Connectivity" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

DNS for IPv6

IPv6 supports Domain Name System (DNS) record types in the DNS name-to-address and address-to-name lookup processes. The DNS AAAA resource record types support IPv6 addresses and are equivalent to an A address record in IPv4. The switch supports DNS resolution for IPv4 and IPv6.

Path MTU Discovery for IPv6 Unicast

The switch supports advertising the system maximum transmission unit (MTU) to IPv6 nodes and path MTU discovery. Path MTU discovery allows a host to dynamically discover and adjust to differences in the MTU size of every link along a given data path. In IPv6, if a link along the path is not large enough to accommodate the packet size, the source of the packet handles the fragmentation. The switch does not support path MTU discovery for multicast packets.

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.

Default Router Preference

The switch supports IPv6 default router preference (DRP), an extension in router advertisement messages. DRP improves the ability of a host to select an appropriate router, especially when the host is multihomed and the routers are on different links. The switch does not support the Route Information Option in RFC 4191.

An IPv6 host maintains a default router list from which it selects a router for traffic to offlink destinations. The selected router for a destination is then cached in the destination cache. NDP for IPv6 specifies that routers that are reachable or probably reachable are preferred over routers whose reachability is unknown or suspect. For reachable or probably reachable routers, NDP can either select the same router every time or cycle through the router list. By using DRP, you can configure an IPv6 host to prefer one router over another, provided both are reachable or probably reachable.

For more information about DRP for IPv6, see the "Implementing IPv6 Addresses and Basic Connectivity" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

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

•Ping, traceroute, Telnet, and TFTP

•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 hardware memory usage to both IPv4 and IPv6 protocols.

Figure 38-1 shows a router forwarding both IPv4 and IPv6 traffic through the same interface, based on the IP packet and destination addresses.

Figure 38-1 Dual IPv4 and IPv6 Support on an Interface

Use the dual IPv4 and IPv6 switch database management (SDM) template to enable IPv6 routing dual stack environments (supporting both IPv4 and IPv6). For more information about the dual IPv4 and IPv6 SDM template, see Chapter 7 "Configuring SDM Templates."

•If you try to configure IPv6 without first selecting a dual IPv4 and IPv6 template, a warning message appears.

•In IPv4-only environments, the switch routes IPv4 packets and applies IPv4 QoS and ACLs in hardware. IPv6 packets are not supported.

•In dual IPv4 and IPv6 environments, the switch routes both IPv4 and IPv6 packets and applies IPv4 QoS in hardware.

•IPv6 QoS is not supported.

•If you do not plan to use IPv6, do not use the dual stack template because it results in less hardware memory availability for each resource.

For more information about IPv4 and IPv6 protocol stacks, see the "Implementing IPv6 Addressing and Basic Connectivity" chapter of Cisco IOS IPv6 Configuration Library on Cisco.com.

DHCP for IPv6 Address Assignment

DHCPv6 enables DHCP servers to pass configuration parameters, such as IPv6 network addresses, to IPv6 clients. The address assignment feature manages nonduplicate address assignment in the correct prefix based on the network where the host is connected. Assigned addresses can be from one or multiple prefix pools. Additional options, such as default domain and DNS name-server address, can be passed back to the client. Address pools can be assigned for use on a specific interface, on multiple interfaces, or the server can automatically find the appropriate pool.

Beginning with Cisco IOS Release 12.2(58)SE, switches running the metro IP access image support these features:

•DHCPv6 Bulk Lease Query

DHCPv6 bulk-lease query allows a client to request information about DHCPv6 bindings. This functionality adds new query types and allows the bulk transfer of DHCPv6 binding data through TCP. Bulk transfer of DHCPv6 binding data is useful when the relay server switch is rebooted and the relay server has lost all the binding information because after the reboot, the relay server automatically generates a Bulk Lease Query to get the binding information from DHCP server.

•DHCPv6 Relay Source Configuration

The DHCPv6 server replies to the source address of the DHCP relay agent. Typically, messages from a DHCPv6 relay agent show the source address of the interface from which they are sent. However, in some networks, it may be desirable to configure a more stable address (such as a loopback interface) as the source address for messages from the relay agent. The DHCPv6 Relay Source Configuration feature provides this capability.

For more information and to configure these features, see the Cisco IOS IPv6 Configuration Guide, Release 12.4.

This document describes only the DHCPv6 address assignment. For more information about configuring the DHCPv6 client, server, or relay agent functions, see the "Implementing DHCP for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

DHCP for IPv6 Server, Client, and Relay

Beginning with Cisco IOS Release 12.2(58)SE, the switch supports IPv6 DHCP in a VRF environment with limited VRF flexibility.

For more information about configuring the DHCPv6 client, server, or relay agent functions, see the "Implementing DHCP for IPv6" chapter in the Cisco IOS IPv6 Configuration Guide on Cisco.com.

Static Routes for IPv6

Static routes are manually configured and define an explicit route between two networking devices. Static routes are useful for smaller networks with only one path to an outside network or to provide security for certain types of traffic in a larger network.

For more information about static routes, see the "Implementing Static Routes for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

RIP for IPv6

Routing Information Protocol (RIP) for IPv6 is a distance-vector protocol that uses hop count as a routing metric. It includes support for IPv6 addresses and prefixes and the all-RIP-routers multicast group address FF02::9 as the destination address for RIP update messages.

For more information about RIP for IPv6, see the "Implementing RIP for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

OSPF for IPv6

The switch supports Open Shortest Path First (OSPF) for IPv6, a link-state protocol for IP. For more information, see the "Implementing OSFP for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

EIGRP IPv6

The switch supports Enhanced Interior Gateway Routing Protocol (EIGRP) for IPv6. It is configured on the interfaces on which it runs and does not require a global IPv6 address.

Before running, an instance of EIGRP IPv6 requires an implicit or explicit router ID. An implicit router ID is derived from a local IPv4 address, so any IPv4 node always has an available router ID. However, EIGRP IPv6 might be running in a network with only IPv6 nodes and therefore might not have an available IPv4 router ID.

For more information about EIGRP for IPv6, see the "Implementing EIGRP for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Multiprotocol BGP for IPv6

Multiprotocol Border Gateway Protocol (BGP) is the supported exterior gateway protocol for IPv6. Multiprotocol BGP extensions for IPv6 support the same features and functionality as IPv4 BGP. IPv6 enhancements to multiprotocol BGP include support for IPv6 address family and network layer reachability information (NLRI) and next-hop (the next router in the path to the destination) attributes that use IPv6 addresses.

The switch does not support multicast BGP or non-stop forwarding (NSF) for IPv6 or for BGP IPv6.

For more information about configuring BGP for IPv6, see the "Implementing Multiprotocol BGP for IPv6" chapter in the Cisco IOS IPv6 Configuration Guide on Cisco.com.

SNMP and Syslog Over IPv6

To support both IPv4 and IPv6, IPv6 network management requires both IPv6 and IPv4 transports. Syslog over IPv6 supports address data types for these transports.

SNMP and syslog over IPv6 provide these features:

•Support for both IPv4 and IPv6

•IPv6 transport for SNMP and to modify the SNMP agent to support traps for an IPv6 host

•SNMP- and syslog-related MIBs to support IPv6 addressing

•Configuration of IPv6 hosts as trap receivers

For support over IPv6, SNMP modifies the existing IP transport mapping to simultaneously support IPv4 and IPv6. These SNMP actions support IPv6 transport management:

•Opens User Datagram Protocol (UDP) SNMP socket with default settings

•Provides a new transport mechanism called SR_IPV6_TRANSPORT

•Sends SNMP notifications over IPv6 transport

•Supports SNMP-named access lists for IPv6 transport

•Supports SNMP proxy forwarding using IPv6 transport

•Verifies SNMP Manager feature works with IPv6 transport

For information on SNMP over IPv6, including configuration procedures, see the "Managing Cisco IOS Applications over IPv6" chapter in the Cisco IOS IPv6 Configuration Guide on Cisco.com.

For information about syslog over IPv6, including configuration procedures, see the "Implementing IPv6 Addressing and Basic Connectivity" chapter in the Cisco IOS IPv6 Configuration Guide on Cisco.com.

HTTP(S) Over IPv6

The HTTP client sends requests to both IPv4 and IPv6 HTTP servers, which respond to requests from both IPv4 and IPv6 HTTP clients. URLs with literal IPv6 addresses must be specified in hexadecimal using 16-bit values between colons.

The accept socket call chooses an IPv4 or IPv6 address family. The accept socket is either an IPv4 or IPv6 socket. The listening socket waits for both IPv4 and IPv6 signals that indicate a connection. The IPv6 listening socket is bound to an IPv6 wildcard address.

The underlying TCP/IP stack supports a dual-stack environment. HTTP relies on the TCP/IP stack and the sockets for processing network-layer interactions.

Basic network connectivity (ping) must exist between the client and the server hosts before HTTP connections can be made.

For more information, see the "Managing Cisco IOS Applications over IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Multi-Protocol VRF (VRF-Lite) for IPv6

The switch supports IPv4 Multi-Protocol VRF-CE (also referred to as VRF-Lite). See the "Configuring Multi-VRF CE" section. Beginning with Cisco IOS Release 12.2(58)SE, the switches running the metro IP access image also support a similar feature for IPv6. IPv6 VRF-Lite supports partial MPLS-VRF PE functionality, which allows overlapping IPv6 unicast addresses across different VRFs. VRF-Lite does not support MPLS label exchange, LDP adjacency, or MPLS labels. Typically VRF-Lite uses a trunk port between a PE and CE device to extend some MPLS PE functionality to the CE, and then allows multiple customers to share the same CE device. VRF-Lite allows a service provider to support two or more VPNs with overlapping IP addresses using one interface.

The switch supports these VRF-Lite features on all interfaces:

•Configuration of a single VRF for both IPv4 and IPv6 on the same interface

•Static routing and external BGP (eBGP)

•VRF-aware route applications: ping, traceroute, and Telnet

•VPNs that support both IPv4 and IPv6 traffic

•Up to 26 different VRFs. However, the total number of VRF routes supported might be less, depending on the number of interfaces (SVIs or routed ports) per VRF.

The switch does not support these VFR-aware IPv6 protocols: iBGP, OSPFv3, ISIS, EIGRP, or RIP.

To support IPv6 VRF-Lite, the switch must be running either the IPv4-and-IPv6 default SDM template or the IPv4-and-IPv6 routing template. For IPv6 VRF-Lite, the switch supports approximately 500 routes with the IPv4-and-IPv6 default template and 1800 routes with the IPv4-and-IPv6 routing template. Routes that do not fit into the routing table are put in a retry queue. Enter the show platform ipv6 unicast retry route privileged EXEC command to see any routes in the retry queue.

The IPv4 Multi-VRF-Lite commands apply only to IPv4 traffic. The IPv6 VRF-Lite commands work with both IPv6 and IPv4 VRF. You can use the same VRF name for IPv4 and IPv6 traffic. If you anticipate the need to add IPv6 traffic to your existing network, you can migrate your IPv4 VRFs to allow IPv6traffic by using the vrf upgrade-cli multi-af-mode {common-policies | non-common policies} [vrf vrf-name] global configuration command and configuring IPv6 address families.

Note Although you can continue to configure IPv4 VRFs by using the IPv4-specific commands described in the "Configuring Multi-VRF CE" section, we recommend that you use the IPv6 commands to facilitate future compatibility.

See the "Configuring Multi-Protocol VRF for IPv6" section for the configuring process.

Unsupported IPv6 Unicast Routing Features

•IPv6 policy-based routing

•Full IPv6 virtual private network (VPN) routing and forwarding (VRF) table support

Note The switch supports IPv6 VRF-Lite (Multi-VRF-CE), which is IPv6 VPN in a VRF environment with limited VRF functionality.

•Support for Intermediate System-to-Intermediate System (IS-IS) routing

•IPv6 packets destined to site-local addresses

•Tunneling protocols, such as IPv4-to-IPv6 or IPv6-to-IPv4

•The switch as a tunnel endpoint supporting IPv4-to-IPv6 or IPv6-to-IPv4 tunneling protocols

•IPv6 unicast reverse-path forwarding

•IPv6 general prefixes

•HSRP for IPv6

Limitations

Because IPv6 is implemented in switch hardware, some limitations occur due to the IPv6 compressed addresses in the hardware memory. This results in some loss of functionality and limits some features.

•When using user-network interface (UNI) or enhanced network interface (ENI) ports for any IPv6-related features, you must first globally enable IP routing and IPv6 routing on the switch by entering the ip routing and ipv6 unicast-routing global configuration commands even if you are not using IPv6 routing.

•ICMPv6 redirect functionality is not supported for IPv6 host routes (routes used to reach a specific host) or for IPv6 routes with masks greater than 64 bits. The switch cannot redirect hosts to a better first-hop router for a specific destination that is reachable through a host route or through a route with masks greater than 64 bits.

•Load balancing using equal cost and unequal cost routes is not supported for IPv6 host routes or for IPv6 routes with a mask greater than 64 bits.

•The switch cannot forward SNAP-encapsulated IPv6 packets.

Note There is a similar limitation for IPv4 SNAP-encapsulated packets, but the packets are dropped at the switch.

•The switch routes IPv6-to-IPv4 and IPv4-to-IPv6 packets in hardware, but the switch cannot be an IPv6-to-IPv4 or IPv4-to-IPv6 tunnel endpoint.

•Bridged IPv6 packets with hop-by-hop extension headers are forwarded in software. In IPv4, these packets are routed in software but bridged in hardware.

•In addition to the normal SPAN and RSPAN limitations defined in the software configuration guide, these limitations are specific to IPv6 packets:

–When you send RSPAN IPv6-routed packets, the source MAC address in the SPAN output packet might be incorrect.

–When you send RSPAN IPv6-routed packets, the destination MAC address might be incorrect. Normal traffic is not affected.

•The switch cannot apply QoS classification or policy-based routing on source-routed IPv6 packets in hardware.

•The switch cannot generate ICMPv6 Packet Too Big messages for multicast packets.

•When using IPv6 VRF Lite, the switch supports approximately 500 routes with the IPv4-and-IPv6 default template and 1800 routes with the IPv4-and-IPv6 routing template. Routes that do not fit into the routing table are put in a retry queue.

•IPv6 unicast routing and IPv6 VRF Lite share the same allocation region of TCAM for IPv6 route entries. If IPv6 routing protocols in the IPv6 global table are enabled before IPv6 VRF-Lite, the routing protocols can install so many route entries that IPv6 VRF Lite default routes no longer fit in the TCAM. To ensure that IPv6 VRF Lite functions correctly, you should enter at least one IPv6 vrf definition global configuration command with an IPv6 address family before configuring the IPv6 routing protocols and before configuring any IPv6 addresses on any interfaces.

Configuring IPv6

•Default IPv6 Configuration

•Configuring IPv6 Addressing and Enabling IPv6 Routing

•Configuring Default Router Preference

•Configuring IPv4 and IPv6 Protocol Stacks

•Configuring DHCP for IPv6 Address Assignment

•Configuring DHCP Client, Server and Relay Functions

•Configuring IPv6 ICMP Rate Limiting

•Configuring CEF for IPv6

•Configuring Static Routes for IPv6

•Configuring RIP for IPv6

•Configuring OSPF for IPv6

•Configuring EIGRP for IPv6

•Configuring BGP for IPv6

•Configuring Multi-Protocol VRF for IPv6

Default IPv6 Configuration

Table 38-1 shows the default IPv6 configuration.

Configuring IPv6 Addressing and Enabling IPv6 Routing

Follow these rules or limitations when configuring IPv6 on the switch:

•Be sure to select a dual IPv4 and IPv6 SDM template.

•Not all features discussed in this chapter are supported by the switch. See the "Unsupported IPv6 Unicast Routing Features" section.

•In the ipv6 address interface configuration command, you must enter the ipv6-address and ipv6-prefix variables with the address specified in hexadecimal using 16-bit values between colons. The prefix-length variable (preceded by a slash [/]) is a decimal value that shows how many of the high-order contiguous bits of the address comprise the prefix (the network portion of the address).

To forward IPv6 traffic on an interface, you must configure a global IPv6 address on that interface. Configuring an IPv6 address on an interface automatically configures a link-local address and activates IPv6 for the interface. The configured interface automatically joins these required multicast groups for that link:

•solicited-node multicast group FF02:0:0:0:0:1:ff00::/104 for each unicast address assigned to the interface (the address for the neighbor discovery process.)

•all-nodes link-local multicast group FF02::1

•all-routers link-local multicast group FF02::2

For more information about configuring IPv6 routing, see the "Implementing Addressing and Basic Connectivity for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Beginning in privileged EXEC mode, follow these steps to assign an IPv6 address to a Layer 3 interface and enable IPv6 routing:

To remove an IPv6 address from an interface, use the no ipv6 address ipv6-prefix/prefix length eui-64 or no ipv6 address ipv6-address link-local interface configuration command. To remove all manually configured IPv6 addresses from an interface, use the no ipv6 address interface configuration command without arguments. To disable IPv6 processing on an interface that has not been explicitly configured with an IPv6 address, use the no ipv6 enable interface configuration command. To globally disable IPv6 routing, use the no ipv6 unicast-routing global configuration command.

This example shows how to enable IPv6 with both a link-local address and a global address based on the IPv6 prefix 2001:0DB8:c18:1::/64. The EUI-64 interface ID is used in the low-order 64 bits of both addresses. Output from the show ipv6 interface EXEC command is included to show how the interface ID (20B:46FF:FE2F:D940) is appended to the link-local prefix FE80::/64 of the interface.

Switch(config)# sdm prefer dual-ipv4-and-ipv6 default 

Switch(config)# ipv6 unicast-routing

Switch(config)# interface gigabitethernet0/2

Switch(config-if)# no switchport

Switch(config-if)# ipv6 address 2001:0DB8:c18:1::/64 eui 64

Switch(config-if)# end

Switch# show ipv6 interface gigabitethernet0/11

GigabitEthernet0/2 is up, line protocol is up

  IPv6 is enabled, link-local address is FE80::20B:46FF:FE2F:D940

  Global unicast address(es):

  2001:0DB8:c18:1:20B:46FF:FE2F:D940, subnet is 2001:0DB8:c18:1::/64 [EUI]

  Joined group address(es):

    FF02::1

    FF02::2

    FF02::1:FF2F:D940

  MTU is 1500 bytes

  ICMP error messages limited to one every 100 milliseconds

  ICMP redirects are enabled

  ND DAD is enabled, number of DAD attempts: 1

  ND reachable time is 30000 milliseconds

  ND advertised reachable time is 0 milliseconds

  ND advertised retransmit interval is 0 milliseconds

  ND router advertisements are sent every 200 seconds

  ND router advertisements live for 1800 seconds

  Hosts use stateless autoconfig for addresses.

Configuring Default Router Preference

Router advertisement messages are sent with the default router preference (DRP) configured by the ipv6 nd router-preference interface configuration command. If no DRP is configured, router advertisements are sent with a medium preference.

A DRP is useful when two routers on a link might provide equivalent, but not equal-cost routing, and policy might dictate that hosts should prefer one of the routers.

Beginning in privileged EXEC mode, follow these steps to configure a DRP for a router on an interface.

Use the no ipv6 nd router-preference interface configuration command to disable an IPv6 DRP.

This example shows how to configure a DRP of high for the router on an interface.

Switch# configure terminal

Switch(config)# interface gigabitethernet0/1

Switch(config-if)# ipv6 nd router-preference high

Switch(config-if)# end

For more information about configuring DRP for IPv6, see the "Implementing IPv6 Addresses and Basic Connectivity" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Configuring IPv4 and IPv6 Protocol Stacks

Before configuring IPv6 routing, you must select an SDM template that supports IPv4 and IPv6. If not already configured, use the sdm prefer dual-ipv4-and-ipv6 {default | routing | vlan} global configuration command to configure a template that supports IPv6. When you select a new template, you must reload the switch by using the reload privileged EXEC command so that the template takes effect.

Beginning in privileged EXEC mode, follow these steps to configure a Layer 3 interface to support both IPv4 and IPv6 and to enable IPv6 routing.

To disable IPv4 routing, use the no ip routing global configuration command. To disable IPv6 routing, use the no ipv6 unicast-routing global configuration command. To remove an IPv4 address from an interface, use the no ip address ip-address mask interface configuration command. To remove an IPv6 address from an interface, use the no ipv6 address ipv6-prefix/prefix length eui-64 or no ipv6 address ipv6-address link-local interface configuration command. To remove all manually configured IPv6 addresses from an interface, use the no ipv6 address interface configuration command without arguments. To disable IPv6 processing on an interface that has not been explicitly configured with an IPv6 address, use the no ipv6 enable interface configuration command.

This example shows how to enable IPv4 and IPv6 routing on an interface.

Switch(config)# sdm prefer dual-ipv4-and-ipv6 default 

Switch(config)# ip routing

Switch(config)# ipv6 unicast-routing

Switch(config)# interface gigabitethernet0/2

Switch(config-if)# no switchport

Switch(config-if)# ip address 192.168.99.1 244.244.244.0

Switch(config-if)# ipv6 address 2001:0DB8:c18:1::/64 eui 64

Switch(config-if)# end

Configuring DHCP for IPv6 Address Assignment

•Default DHCPv6 Address Assignment Configuration

•DHCPv6 Address Assignment Configuration Guidelines

•Enabling the DHCPv6 Server Address-Assignment

•Enabling the DHCPv6 Client Address Assignment

Default DHCPv6 Address Assignment Configuration

By default, no Dynamic Host Configuration Protocol for IPv6 (DHCPv6) features are configured on the switch.

DHCPv6 Address Assignment Configuration Guidelines

When configuring a DHCPv6 address assignment, consider these guidelines:

•In the procedures, the specified interface must be one of these Layer 3 interfaces:

–DHCPv6 IPv6 routing must be enabled on a Layer 3 interface.

–SVI: a VLAN interface created by using the interface vlan vlan_id command.

–EtherChannel port channel in Layer 3 mode: a port-channel logical interface created by using the interface port-channel port-channel-number command.

•Before configuring DHCPv6, you must select a Switch Database Management (SDM) template that supports IPv4 and IPv6.

•The switch can act as a DHCPv6 client, server, or relay agent. The DHCPv6 client, server, and relay function are mutually exclusive on an interface.

Enabling the DHCPv6 Server Address-Assignment

Beginning in privileged EXEC mode, follow these steps to enable the DHCPv6 server function on an interface.

To delete a DHCPv6 pool, use the no ipv6 dhcp pool poolname global configuration command. Use the no form of the DHCP pool configuration mode commands to change the DHCPv6 pool characteristics. To disable the DHCPv6 server function on an interface, use the no ipv6 dhcp server interface configuration command.

This example shows how to configure a pool called engineering with an IPv6 address prefix:

Switch# configure terminal

Switch(config)# ipv6 dhcp pool engineering

Switch(config-dhcpv6)#address prefix 2001:1000::0/64

Switch(config-dhcpv6)# end

This example shows how to configure a pool called testgroup with three link-addresses and an IPv6 address prefix:

Switch# configure terminal

Switch(config)# ipv6 dhcp pool testgroup

Switch(config-dhcpv6)# link-address 2001:1001::0/64

Switch(config-dhcpv6)# link-address 2001:1002::0/64

Switch(config-dhcpv6)# link-address 2001:2000::0/48

Switch(config-dhcpv6)# address prefix 2001:1003::0/64

Switch(config-dhcpv6)# end

This example shows how to configure a pool called 350 with vendor-specific options:

Switch# configure terminal

Switch(config)# ipv6 dhcp pool 350

Switch(config-dhcpv6)# address prefix 2001:1005::0/48

Switch(config-dhcpv6)# vendor-specific 9

Switch(config-dhcpv6-vs)# suboption 1 address 1000:235D::1

Switch(config-dhcpv6-vs)# suboption 2 ascii "IP-Phone"

Switch(config-dhcpv6-vs)# end

Enabling the DHCPv6 Client Address Assignment

Beginning in privileged EXEC mode, follow these steps to enable the DHCPv6 client function on an interface.

To disable the DHCPv6 client function, use the no ipv6 address dhcp interface configuration command. To remove the DHCPv6 client request, use the no ipv6 address dhcp client request interface configuration command.

This example shows how to acquire an IPv6 address and to enable the rapid-commit option:

Switch(config)# interface gigabitethernet0/1

Switch(config-if)# ipv6 address dhcp rapid-commit

This document describes only the DHCPv6 address assignment. For more information about configuring the DHCPv6 client, server, or relay agent functions, see the "Implementing DHCP for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Configuring DHCP Client, Server and Relay Functions

For more information about configuring the DHCPv6 client, server, and relay agent functions, see the "Implementing DHCP for IPv6" chapter in the Cisco IOS IPv6 Configuration Guide on Cisco.com.

http://www.cisco.com/en/US/docs/ios-xml/ios/ipv6/configuration/12-4t/ip6-dhcp.html

In Cisco IOS Release 12.2(58)SE, on the switch has limited VRF flexibility. It supports DHCP VRF-aware configuration in a VRF environment, but operates as VRF-unaware DHCPv6.

Configuration guidelines:

•In the VRF environment, all DHCPv6 server, relay, and client devices are different devices running DHCPv6:

–The DHCP relay agent forwards client requests to the DHCP server.

–The DHCP server uses its global configuration pool to respond to the client request.

•The DHCPv6 server can be shared by multiple VRF DHCP clients or by different location VRFs, or each VRF client can use a different DHCPv6 server.

•When you configure this feature, you should perform VRF configuration before you configure DHCPv6 client, server, and relay.

Configuring IPv6 ICMP Rate Limiting

ICMP rate limiting is enabled by default with a default interval between error messages of 100 milliseconds and a bucket size (maximum number of tokens to be stored in a bucket) of 10.

Beginning in privileged EXEC mode, follow these steps to change the ICMP rate-limiting parameters:

To return to the default configuration, use the no ipv6 icmp error-interval global configuration command.

This example shows how to configure an IPv6 ICMP error message interval of 50 milliseconds and a bucket size of 20 tokens.

Switch(config)#ipv6 icmp error-interval 50 20

Configuring CEF for IPv6

Cisco Express Forwarding (CEF) is a Layer 3 IP switching technology, allowing more CPU processing power to be dedicated to packet forwarding. IPv4 CEF is enabled by default. IPv6 CEF is disabled by default, but automatically enabled when you configure IPv6 routing.

To route IPv6 unicast packets, first globally configure forwarding of IPv6 unicast packets by using the ipv6 unicast-routing global configuration command. You must also configure an IPv6 address and IPv6 processing on an interface by using the ipv6 address interface configuration command.

To disable IPv6 CEF, use the no ipv6 cef global configuration command. To reenable IPv6 CEF, use the ipv6 cef global configuration command. You can verify the IPv6 state by entering the show ipv6 cef privileged EXEC command.

For more information about configuring CEF, see the "Implementing IPv6 Addressing and Basic Connectivity" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Configuring Static Routes for IPv6

Before configuring a static IPv6 route, you must:

•Enable routing by using the ip routing global configuration command.

•Enable the forwarding of IPv6 packets by using the ipv6 unicast-routing global configuration command.

•Enable IPv6 on at least one Layer 3 interface by configuring an IPv6 address on the interface.

Beginning in privileged EXEC mode, follow these steps to configure an IPv6 static route:

To remove a configured static route, use the no ipv6 route ipv6-prefix/prefix length {ipv6-address | interface-id [ipv6-address]} [administrative distance] global configuration command.

This example shows how to configure a floating static route to an interface. The route has an administrative distance of 130:

Switch(config)# ipv6 route 2001:0DB8::/32 gigabitethernet0/1 130

For more information about configuring static IPv6 routing, see the "Implementing Static Routes for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Configuring RIP for IPv6

Before configuring the switch to run IPv6 RIP, you must:

•Enable routing by using the ip routing global configuration command.

•Enable the forwarding of IPv6 packets by using the ipv6 unicast-routing global configuration command.

•Enable IPv6 on any Layer 3 interfaces on which IPv6 RIP is to be enabled.

Beginning in privileged EXEC mode, follow these required and optional steps to configure IPv6 RIP:

To disable a RIP routing process, use the no ipv6 router rip name global configuration command. To disable the RIP routing process for an interface, use the no ipv6 rip name interface configuration command.

This example shows how to enable the RIP routing process cisco with a maximum of eight equal-cost routes and to enable it on an interface:

Switch(config)# ipv6 router rip cisco

Switch(config-router)# maximum-paths 8

Switch(config)# exit

Switch(config)# interface gigabitethernet0/3

Switch(config-if)# ipv6 rip cisco enable

For more information about configuring RIP routing for IPv6, see the "Implementing RIP for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com

Configuring OSPF for IPv6

You can customize OSPF for IPv6 for your network. However, the defaults are set to meet the requirements of most customers and features.

Follow these guidelines:

•Be careful when changing the defaults for IPv6 commands. Doing so might adversely affect OSPF for the IPv6 network.

•Before you enable IPv6 OSPF on an interface, you must:

–Enable routing by using the ip routing global configuration command.

–Enable the forwarding of IPv6 packets by using the ipv6 unicast-routing global configuration command.

–Enable IPv6 on Layer 3 interfaces on which you are enabling IPv6 OSPF.

Beginning in privileged EXEC mode, follow these required and optional steps to configure IPv6 OSPF:

To disable an OSPF routing process, use the no ipv6 router ospf process-id global configuration command. To disable the OSPF routing process for an interface, use the no ipv6 ospf process-id area area-id interface configuration command.

For more information about configuring OSPF routing for IPv6, see the "Implementing OSPF for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Configuring EIGRP for IPv6

EIGRP for IPv6 is enabled when you configure the ipv6 router eigrp as-number command and ipv6 eigrp as-number command on the interface.

To set an explicit router ID, use the show ipv6 eigrp command to identify the configured router IDs, and then use the eigrp router-id ip-address command.

As with EIGRP IPv4, you can use EIGRPv6 to specify your EIGRP IPv4 interfaces and to select a subset of those as passive interfaces. Use the passive-interface default command to make all interfaces passive, and then use the no passive-interface command on selected interfaces to make them active. EIGRP IPv6 does not need to be configured on a passive interface.

For more configuration procedures, see the "Implementing EIGRP for IPv6" chapter in the Cisco IOS IPv6 Configuration Library on Cisco.com.

Configuring BGP for IPv6

When configuring multiprotocol BGP extensions for IPv6, you must create the BGP routing process, configure peering relationships, and customize BGP for your particular network. Note that BGP functions the same in IPv6 as in IPv4. Before configuring the router to run BGP for IPv6, you must use the ipv6 unicast-routing command to globally enable IPv6 routing.

Beginning in privileged EXEC mode, follow these steps to configure IPv6 BGP:

For more configuration procedures, see the "Implementing Multiprotocol BGP for IPv6" chapter in the Cisco IOS IPv6 Configuration Guide on Cisco.com.

http://www.cisco.com/en/US/docs/ios/ipv6/configuration/guide/12_4/ipv6_12_4_book.html

The switch does not support multicast IPv6 BGP, nonstop forwarding (NSF) for IPv6 BGP, 6PE multipath (EoMPLS), or IPv6 VRF.

Configuring Multi-Protocol VRF for IPv6

To support IPv6 VRF-Lite, the switch must be running the IP access image and either the IPv4-and-IPv6 default SDM template or the IPv4-and-IPv6 routing template.

Note Because some IPv6 indirect routes can use more than one TCAM entry, the total number of supported indirect routes might be less than that shown in the template. If the limit of TCAM entries for IPv6 routes is exceeded, an error message is generated.

Configuring VRF-Lite includes these steps:

•Configure IPv6 VRFs.

Enter the vrf definition vrf-name global configuration command to enter VRF configuration mode and to configure the VRF.

•Associate interfaces (for customer VPNs and PE devices) to the defined VRFs.

In interface configuration mode, enter the vrf forwarding vrf-name command to bind the VRF to the interface.

•Populate the VRF with static routes or eBGP routes.

For complete information about the commands in this section, see the Cisco IOS IPv6 Command Reference at:
http://www.cisco.com/en/US/docs/ios/ipv6/command/reference/ipv6_book.html

The IPv4 Multi-VRF-Lite commands apply only to IPv4 traffic. The IPv6 VRF-Lite commands work with both IPv6 and IPv4 VRF. You can use the same VRF name for IPv4 and IPv6 traffic. If you anticipate the need to add IPv6 traffic to your existing network, you can migrate your IPv4 VRFs to allow IPv6traffic by using the vrf upgrade-cli multi-af-mode {common-policies | non-common policies} [vrf vrf-name] global configuration command and configuring IPv6 address families.

Note Although you can continue to use the IPv4-specific commands to configure IPv4 VRFs, using the IPv6 commands allows you to configure both IPv4 and IPv6 VRFs. We recommend that you use the IPv6 commands to facilitate future compatibility.

Beginning in privileged EXEC mode, follow these steps to configure one or more IPv6 VRFs.

Use the no vrf definition vrf-name global configuration command to delete a VRF and to remove all interfaces from it. Use the no vrf forwarding interface configuration command to remove an interface from the VRF.

This example shows the steps required for configuring IPv6 VRF Lite. It requires that the IPv4 and IPv6 default or routing template be configured.

Enable IPv6 VRF Lite:

Switch(config)# ip routing

Switch(config)# ipv6 unicast-routing

Switch(config)# vrf definition abc

Switch(config-vrf)# rd 100:2

Switch(config-vrf)# address-family ipv4

Switch(config-vrf-af)# exit

Switch(config-vrf)# address-family ipv6

Switch(config-vrf-af)# exit

Switch(config-vrf)# exit

Associate the VRF with a routed interface:

Switch(config)# interface gigabitethernet0/1

Switch(config-if)# vrf forwarding abc

Switch(config-if)# no switchport

Switch(config-if)# no ip address

Switch(config-if)# ipv6 address 2000::1/64

Switch(config-if)# exit

Associate the VRF with an SVI interface:

Switch(config)# vlan 200

Switch(config-vlan)# exit

Switch(config)# interface vlan 200

Switch(config-if)# vrf forwarding abc

Switch(config-if)# no ip address

Switch(config-if)# ipv6 address 2000::1/64

Switch(config-if)# exit

Switch(config)# interface gigabitethernet0/2

Switch(config-if)# switchport trunk allowed vlan 200

Switch(config-if)# switchport mode trunk

Switch(config-if)# exit

Enable BGP routing protocol for IPv6 VRF Lite:

Switch(config)# router bgp 1 

Switch(config-router)# bgp router-id 1.1.1.1 

Switch(config-router)# address-family ipv6 vrf ABC 

Switch(config-router-af)# redistribute connected 

Switch(config-router-af)# neighbor 2000::2 remote-as 1

Switch(config-router-af)# neighbor 2000::2 activate

Switch(config-router-af)# exit 

Switch(config-router)# exit

Switch(config)# ipv6 route vrf ABC 4000::/64 5000::1

Note The last command configures a static route pointing to the customer router.

Verify connectivity:

Switch# ping vrf abc 2000::2

Switch# telnet 2222::2 /vrf abc

Switch# traceroute vrf abc2222::2

Displaying IPv6

For complete syntax and usage information on these commands, see the Cisco IOS command reference publications.

This is an example of the output from the show ipv6 interface privileged EXEC command:

Switch# show ipv6 interface

Vlan1 is up, line protocol is up

  IPv6 is enabled, link-local address is FE80::20B:46FF:FE2F:D940

  Global unicast address(es):

    3FFE:C000:0:1:20B:46FF:FE2F:D940, subnet is 3FFE:C000:0:1::/64 [EUI]

  Joined group address(es):

    FF02::1

    FF02::2

    FF02::1:FF2F:D940

  MTU is 1500 bytes

  ICMP error messages limited to one every 100 milliseconds

  ICMP redirects are enabled

  ND DAD is enabled, number of DAD attempts: 1

  ND reachable time is 30000 milliseconds

  ND advertised reachable time is 0 milliseconds

  ND advertised retransmit interval is 0 milliseconds

  ND router advertisements are sent every 200 seconds

  ND router advertisements live for 1800 seconds

<output truncated>

This is an example of the output from the show ipv6 cef privileged EXEC command:

Switch# show ipv6 cef

::/0

  nexthop 3FFE:C000:0:7::777 Vlan7

3FFE:C000:0:1::/64

  attached to Vlan1

3FFE:C000:0:1:20B:46FF:FE2F:D940/128

  receive

3FFE:C000:0:7::/64

  attached to Vlan7

3FFE:C000:0:7::777/128

  attached to Vlan7

3FFE:C000:0:7:20B:46FF:FE2F:D97F/128

  receive

3FFE:C000:111:1::/64

  attached to GigabitEthernet0/11

3FFE:C000:111:1:20B:46FF:FE2F:D945/128

  receive

3FFE:C000:168:1::/64

  attached to GigabitEthernet0/43

3FFE:C000:168:1:20B:46FF:FE2F:D94B/128

  receive

3FFE:C000:16A:1::/64

  attached to Loopback10

3FFE:C000:16A:1:20B:46FF:FE2F:D900/128

  receive

<output truncated>

This is an example of the output from the show ipv6 protocols privileged EXEC command:

Switch# show ipv6 protocols

IPv6 Routing Protocol is "connected"

IPv6 Routing Protocol is "static"

IPv6 Routing Protocol is "rip fer"

  Interfaces:

    Vlan6

GigabitEthernet0/4

GigabitEthernet0/11

GigabitEthernet0/12

  Redistribution:

    None

This is an example of the output from the show ipv6 rip privileged EXEC command:

Switch# show ipv6 rip

RIP process "fer", port 521, multicast-group FF02::9, pid 190

     Administrative distance is 120. Maximum paths is 16

     Updates every 30 seconds, expire after 180

     Holddown lasts 0 seconds, garbage collect after 120

     Split horizon is on; poison reverse is off

     Default routes are not generated

     Periodic updates 9040, trigger updates 60

  Interfaces:

    Vlan6

GigabitEthernet0/4

GigabitEthernet0/11

GigabitEthernet0/12

Redistribution:

    None

This is an example of the output from the show ipv6 neighbor privileged EXEC command:

Switch# show ipv6 neighbors

IPv6 Address                              Age Link-layer Addr State Interface

3FFE:C000:0:7::777                          - 0007.0007.0007  REACH Vl7

3FFE:C101:113:1::33                         - 0000.0000.0033  REACH Gi0/13

This is an example of the output from the show ipv6 static privileged EXEC command:

Switch# show ipv6 static

IPv6 Static routes

Code: * - installed in RIB

* ::/0 via nexthop 3FFE:C000:0:7::777, distance 1

This is an example of the output from the show ipv6 route privileged EXEC command:

Switch# show ipv6 route

IPv6 Routing Table - 21 entries

Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP

       U - Per-user Static route

       I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary

       O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2

       ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2

S   ::/0 [1/0]

     via 3FFE:C000:0:7::777

C   3FFE:C000:0:1::/64 [0/0]

     via ::, Vlan1

L   3FFE:C000:0:1:20B:46FF:FE2F:D940/128 [0/0]

     via ::, Vlan1

C   3FFE:C000:0:7::/64 [0/0]

     via ::, Vlan7

L   3FFE:C000:0:7:20B:46FF:FE2F:D97F/128 [0/0]

     via ::, Vlan7

C   3FFE:C000:111:1::/64 [0/0]

     via ::, GigabitEthernet0/11

L   3FFE:C000:111:1:20B:46FF:FE2F:D945/128 [0/0]

C   3FFE:C000:168:1::/64 [0/0]

     via ::, GigabitEthernet0/4

L   3FFE:C000:168:1:20B:46FF:FE2F:D94B/128 [0/0]

     via ::, GigabitEthernet0/4

C   3FFE:C000:16A:1::/64 [0/0]

     via ::, Loopback10

L   3FFE:C000:16A:1:20B:46FF:FE2F:D900/128 [0/0]

     via ::, Loopback10

<output truncated>

This is an example of the output from the show ipv6 traffic privileged EXEC command.

Switch# show ipv6 traffic

IPv6 statistics:

  Rcvd:  1 total, 1 local destination

         0 source-routed, 0 truncated

         0 format errors, 0 hop count exceeded

         0 bad header, 0 unknown option, 0 bad source

         0 unknown protocol, 0 not a router

         0 fragments, 0 total reassembled

         0 reassembly timeouts, 0 reassembly failures

  Sent:  36861 generated, 0 forwarded

         0 fragmented into 0 fragments, 0 failed

         0 encapsulation failed, 0 no route, 0 too big

         0 RPF drops, 0 RPF suppressed drops

  Mcast: 1 received, 36861 sent

ICMP statistics:

  Rcvd: 1 input, 0 checksum errors, 0 too short

        0 unknown info type, 0 unknown error type

        unreach: 0 routing, 0 admin, 0 neighbor, 0 address, 0 port

        parameter: 0 error, 0 header, 0 option

        0 hopcount expired, 0 reassembly timeout,0 too big

        0 echo request, 0 echo reply

        0 group query, 0 group report, 0 group reduce

        1 router solicit, 0 router advert, 0 redirects

        0 neighbor solicit, 0 neighbor advert

  Sent: 10112 output, 0 rate-limited

        unreach: 0 routing, 0 admin, 0 neighbor, 0 address, 0 port

        parameter: 0 error, 0 header, 0 option

        0 hopcount expired, 0 reassembly timeout,0 too big

        0 echo request, 0 echo reply

        0 group query, 0 group report, 0 group reduce

        0 router solicit, 9944 router advert, 0 redirects

        84 neighbor solicit, 84 neighbor advert

UDP statistics:

  Rcvd: 0 input, 0 checksum errors, 0 length errors

        0 no port, 0 dropped

  Sent: 26749 output

TCP statistics:

  Rcvd: 0 input, 0 checksum errors

  Sent: 0 output, 0 retransmitted

This is an example of the output from the show vrf privileged EXEC command showing IPv4 and IPv6 VRFs:

Switch# show vrf brief

  Name                             Default RD          Protocols   Interfaces

  A                                100:1               ipv4       

                                                                   Fa1/0/10

                                                                   Vl200

  ABC                              100:2               ipv4,ipv6   Fa1/0/3

  B                                100:3               ipv4