Managing IPv6 Interfaces

You can manage IPv6 interfaces with the following tasks:

You must configure an IPv6 license using the license ipv6 command before using the IPv6 routing protocol configuration commands on the E Series router. All IPv6 routing protocol configurations are removed from the virtual router when you issue the no ipv6 command.

• Enabling or Disabling an IPv6 Interface
• Clearing IPv6 Interface Counters
• Sending Echo Request Packets to the IPv6 Address
• Discovering the Routes Followed by Router Packets when Traveling to the IPv6 Destination

Enabling or Disabling an IPv6 Interface

You can enable or disable an IPv6 interface at any time.

Before you configure IPv6, you must create the lower-layer interfaces over which IPv6 traffic flows. By default, an IPv6 interface is enabled when you first create it.

To enable an IPv6 interface:

• Issue the ipv6 enable command in Interface Configuration mode.
  host1(config-if)#ipv6 enable

  Use the no version to disable IPv6 on an interface or a subinterface.

Clearing IPv6 Interface Counters

To clear counters on a specified IPv6 interface:

• Issue the clear ipv6 interface command in Privileged Exec mode.

Sending Echo Request Packets to the IPv6 Address

You can send an ICMP echo request packet to the specified IPv6 address for determining reachability by using the ping command.

You can use the source interface keywords to specify a source interface other than the one from which the probe originates. You can use the source address keywords to specify a source IPv6 address other than the one from which the probe originates.

The following characters can appear in the display after you issue the ping command:

• !—Reply received
• .—Timed out while waiting for a reply
• ?—Unknown packet type
• A—Admin unreachable
• b—Packet too big
• H—Host unreachable
• N—Network unreachable
• P—Port unreachable
• p—Parameter problem
• S—Source beyond scope
• t—Hop limit expired (TTL expired)

To send an ICMP echo request packet to the specific IPv6 address:

• Issue the ping command in Privileged Exec mode.
  host1#ping ipv6 1::1

Discovering the Routes Followed by Router Packets when Traveling to the IPv6 Destination

You can discover the routes that router packets follow when traveling to their destination using the traceroute command. You can specify the following parameters in the traceroute command:

• Destination IPv6 address
• Source interface for each of the transmitted packets
• Source IPv6 address for each of the transmitted packets
• Maximum number of hops of the trace and a timeout value
• Size of the IPv6 packets (not the ICMP payload) in the range 0–64000 bytes sent with the traceroute command. Including a size might help locate any MTU problems that exist between your router and a particular device.
• Hop count in the range 1–255; the default is 32

You can also force transmission of the packets on a specified interface regardless of what the IPv6 address lookup indicates. To discover the routes that router packets follow when traveling to their destination:

• Issue the traceroute command in Privileged Exec mode.
  host1#traceroute ipv6 1::1 timeout 10

Related Documentation

• Before You Configure IPv6
• Monitoring General Information for IPv6
• Monitoring Detailed or Summary Information for IPv6 Addresses
• Monitoring Detailed or Summary Information for IPv6 Interfaces
• clear ipv6 interface
• ipv6
• ipv6 enable
• license ipv6
• ping
• traceroute