MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels
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MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels

Last Updated: July 26, 2012

The Static IPv6 Routes over MPLS TE IPv4 Tunnels feature helps to statically enable IPv6 tunneling over Multiprotocol Label Switching (MPLS) traffic engineering (TE) IPv4 tunnels on edge devices. This feature provides a simple and cost-effective method to leverage an existing MPLS IPv4 backbone to integrate IPv6 services over service provider core backbones.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Prerequisites for MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels

  • The MPLS TE feature must be enabled by using the mpls traffic-eng command. This command is disabled by default.
  • A TE tunnel must be configured.

Restrictions for MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels

  • Native TE IPv6 tunnels are not supported.
  • TE IPv4 tunnel exposure to IPv6 Interior Gateway Protocol (IGP) through IPv6 forwarding adjacency or through autoroute announcement is not supported.
  • Static IPv6 routes over TE IPv4 primary autotunnels or autotunnel meshes are not supported.
  • Nonstandard Facilities (NSF), stateful switchover (SSO), and Cisco In-Service Software Upgrade (ISSU) high availability requirements are applicable only for dual Route Processor (RP) platforms.
  • The TE IPv4 tunnel destination cannot be announced to IPv6 routing.
  • TE IPv4 tunnels cannot be announced to IPv6 topologies.
  • The tunnel interface needs both IPv4 and IPv6 addresses to forward IPv6 traffic under the tunnel interface. This is because tunnel interface adjacencies are sourced by the adjacency point-to-point manager, which only expects IPv4 to be enabled on the interface before the adjacency point-to-point manager sources the adjacencies.
  • If the Static IPv6 Routes over MPLS TE IPv4 Tunnels feature is enabled, TE tunnel statistics will show both MPLS and IPv6 statistics because both IPv6 and MPLS adjacencies are created and used.
  • Both the provider-edge-to-customer-edge (PE-to-CE) interface and the CE core-facing interface need IPv6 addresses.
  • MPLS and interface statistics on the tunnel egress interface are not supported.
  • IPv6 policy-based routing on MPLS TE IPv4 tunnels is not supported.
  • Unequal load balancing of IPv6 static routes over multiple TE IPv4 tunnels is not supported.
  • TE IPv4 tunnel autobandwidth is not supported.
  • IPv6 multicast traffic over TE IPv4 point-to-multipoint tunnel is not supported.
  • Generalized MPLS (GMPLS) is not supported.

Information About MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels

Overview of Static IPv6 Routes over MPLS TE IPv4 Tunnels

The Static IPv6 Routes over MPLS TE IPv4 Tunnels feature manually specifies an MPLS TE IPv4 tunnel as an egress interface for IPv6 routes. Communication is established between remote IPv6 domains by using standard IPv6 tunneling mechanism.

The figure below shows two IPv4-aware and IPv6-aware sites, Site 1 and Site 2, which are connected over an MPLS TE IPv4 core. MPLS TE tunnels are set up across the core between endpoints A and B. IPv6 prefixes from Site 1 are routed onto MPLS TE tunnels through edge device A and vice versa, and IPv6 prefixes from Site 2 are routed onto MPLS TE tunnels through edge device B.

Figure 1Static IPv6 Route over MPLS TE IPv4 Tunnels


To carry IPv4 and IPv6 traffic on a single MPLS TE IPv4 tunnel, the MPLS Forwarding Infrastructure (MFI) is enhanced at the tunnel ingress and egress endpoints to differentiate between the two types of traffic.

How to Configure MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels

Assigning an IPv6 Address to an MPLS TE IPv4 Tunnel

To enable a static IPv6 route over an MPLS TE IPv4 tunnel, first configure a TE IPv4 tunnel, and then assign an IPv6 address or IPv6 unnumbered loopback interface to the TE IPv4 tunnel. The steps for these tasks are listed below.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.   interface tunnel interface-number

4.   ip unnumbered loopback interface-number

5.   ipv6 address ipv6-address/prefix-length

6.   end


DETAILED STEPS
 Command or ActionPurpose
Step 1
enable


Example:

Device> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Device# configure terminal

 

Enters global configuration mode.

 
Step 3
interface tunnel interface-number


Example:

Device(config)# interface tunnel 2

 

Configures a tunnel interface and enters interface configuration mode.

 
Step 4
ip unnumbered loopback interface-number


Example:

Device(config-if)# ip unnumbered loopback 0

 

Enables IP processing on an interface without assigning an explicit IP address to the interface.

 
Step 5
ipv6 address ipv6-address/prefix-length


Example:

Device(config-if)# ipv6 address 2001:DB8:2222:7272::72/64

 

Configures an IPv6 address based on an IPv6 general prefix and enables IPv6 processing on an interface.

 
Step 6
end


Example:

Device(config-if)# end

 
 Exits interface configuration mode and returns to privileged EXEC mode.  
What to Do Next

After assigning an IPv6 address to a TE IPv4 tunnel, configure the IPv6 route by using the IPv4 tunnel as the egress interface.

Configuring a Static IPv6 Route by Specifying an MPLS TE IPv4 Tunnel as the Egress Interface

To route IPv6 traffic over a TE IPv4 tunnel, specify the IPv4 tunnel as the egress interface.

Before You Begin

Before configuring an IPv6 route by using a TE IPv4 tunnel as the egress interface, assign an IPv6 address to the TE IPv4 tunnel. For more information, see the "Assigning an IPv6 Address to an MPLS TE IPv4 Tunnel" section.


SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ipv6 route ipv6-address/prefix-length interface-type interface-number

4.   end


DETAILED STEPS
 Command or ActionPurpose
Step 1
enable


Example:

Device> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Device# configure terminal

 

Enters global configuration mode.

 
Step 3
ipv6 route ipv6-address/prefix-length interface-type interface-number


Example:

Device(config)# ipv6 route 2001:DB8:2222:7272::72/64 tunnel 2

 

Implements static IPv6 routes.

Note   Using the ipv6 route command, specify the same tunnel interface-number on which the TE IPv4 tunnel is configured using the steps described in the "Assigning an IPv6 Address to an MPLS TE IPv4 Tunnel" section.
 
Step 4
end


Example:

Device(config)# end

 
 Exits global configuration mode and returns to privileged EXEC mode.  

Verifying IPv6 Routing over a TE IPv4 Tunnel

The IPv6 routing component is responsible for processing the static IPv6 route configuration and updating the IPv6 Routing Information Base (RIB). You can use the commands listed below in any order to verify the IPv6 routing configuration.

SUMMARY STEPS

1.    enable

2.   show ipv6 route

3.   show ipv6 cef interface-type interface-number

4.   exit


DETAILED STEPS
Step 1   enable


Example: 
Device> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.
Step 2   show ipv6 route


Example: 
Device# show ipv6 route

Displays contents of the IPv6 routing table.

Step 3   show ipv6 cef interface-type interface-number


Example: 
Device# show ipv6 cef tunnel 2

Display entries in the IPv6 Forwarding Information Base (FIB).

Step 4   exit


Example: 
Device# exit
Exits privileged EXEC mode.

Displaying IPv6 Statistics over a TE IPv4 Tunnel

When the Static IPv6 Routes over MPLS TE IPv4 Tunnels feature is enabled, the TE IPv4 tunnel can carry both IPv4 and IPv6 traffic. You can display the statistics for IPv6 traffic going over the TE tunnel by using the commands described in this task. These commands can be used in any order. The statistics are displayed on a per-interface, per-protocol basis.


Note
MPLS and interface statistics will be counted twice due to the presence of two midchain adjacencies in the tunnel. You can subtract IPv6 link adjacency statistics (obtained from the show adjacency link ipv6 command) from the interface IPv6 statistics (obtained from the show interface accounting command) to arrive at accurate statistics.
SUMMARY STEPS

1.    enable

2.    show mpls forwarding-table [ipv6-address/prefix-length]

3.    show interfaces accounting

4.    show interface [interface-type interface-number] stats

5.    show adjacency

6.   exit


DETAILED STEPS
Step 1   enable


Example: 
Device> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.
Step 2   show mpls forwarding-table [ipv6-address/prefix-length]


Example: 
Device# show mpls forwarding-table

Displays the contents of MPLS Label FIB (LFIB).

Step 3   show interfaces accounting


Example: 
Device# show interfaces accounting

Displays the number of packets of each protocol type that have been sent through all configured interfaces.

Step 4   show interface [interface-type interface-number] stats


Example: 
Device# show interface stats

Displays numbers of packets that were process switched, fast switched, and distributed switched.

Step 5   show adjacency


Example: 
Device# show adjacency

Displays information about the Cisco Express Forwarding adjacency table or the hardware Layer 3-switching adjacency table.

Step 6   exit


Example: 
Device# exit
Exits privileged EXEC mode.

Troubleshooting IPv6 Routing over a TE IPv4 Tunnel

You can use the following commands for troubleshooting:

  • debug ipv6 cef--Dsplays debug messages for Cisco Express Forwarding for IPv6.
  • debug ipv6 routing--Displays debug messages for IPv6 routing table updates and route cache updates.
  • debug mpls traffic-eng--Displays debug messages for MPLS traffic engineering activities.

Configuration Examples for MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels

Example: Assigning an IPv6 Address to an MPLS TE IPv4 Tunnel

Device> enable
Device# configure terminal
Device(config)# interface tunnel 1
Device(config-if)# ip unnumbered loopback 0
Device(config-if)# ipv6 address 2001:DB8::/32
Device(config-if)# end

Example: Configuring a Static IPv6 Route by Specifying an MPLS TE IPv4 Tunnel as an Egress Interface

Device> enable
Device# configure terminal
Device(config)# ipv6 route 2001:DB8::/32 tunnel 1
Device(config)# end

Additional References

Related Documents

Related Topic Document Title

Cisco IOS commands

Master Commands List, All Releases

MPLS traffic engineering commands

Multiprotocol Label Switching Command Reference

IPv6 commands

IPv6 Command Reference

Technical Assistance

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http://www.cisco.com/cisco/web/support/index.html

Feature Information for MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Table 1Feature Information for MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels
Feature Name Releases Feature Information

MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels

15.2(4)S

The Static IPv6 Routes over MPLS TE IPv4 Tunnels feature helps to statically enable IPv6 tunneling over Multiprotocol Label Switching (MPLS) traffic engineering (TE) IPv4 tunnels through edge devices. This feature provides a simple and cost-effective method to leverage an existing MPLS IPv4 backbone to integrate IPv6 services over service provider core backbones.

Cisco and the Cisco logo are trademarks or registered trademarks of Cisco and/or its affiliates in the U.S. and other countries. To view a list of Cisco trademarks, go to this URL: www.cisco.com/go/trademarks. Third-party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1110R)

Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.

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