- mGRE Tunnel Support over IPv6
- IP over IPv6 Tunnels
- Manually Configured IPv6 over IPv4 Tunnels
- Configuring Physical Interfaces
- Configuring Virtual Interfaces
- Implementing Tunnels
- Tunnel Route Selection
- MPLS VPN over mGRE
- IP Tunnel MIBs
- IF-MIBs
- Synchronous Ethernet (SyncE) ESMC and SSM
- 1+1 SR-APS Without Bridging
- IPv6 Rapid Deployment
- IPv6 Automatic 6to4 Tunnels
- IPv6 over IPv4 GRE Tunnels
- GRE IPv6 Tunnels
- ISATAP Tunnel Support for IPv6
- VRF-Aware Tunnels
- Ethernet over GRE Tunnels
- QoS on Ethernet over GRE Tunnels
- VRF-Aware IPv6 Rapid Deployment Tunnel
- IP Tunnel - GRE Key Entropy Support
- Finding Feature Information
- Information About Manually Configured IPv6 over IPv4 Tunnels
- How to Enable Manually Configured IPv6 over IPv4 Tunnels
- Configuration Examples for Manually Configured IPv6 over IPv4 Tunnels
- Additional References
- Feature Information for Manually Configured IPv6 over IPv4 Tunnels
Manually Configured IPv6 over IPv4 Tunnels
This feature provides support for manually configured IPv6 over IPv4 tunnels. A manually configured tunnel is equivalent to a permanent link between two IPv6 domains over an IPv4 backbone.
- Finding Feature Information
- Information About Manually Configured IPv6 over IPv4 Tunnels
- How to Enable Manually Configured IPv6 over IPv4 Tunnels
- Configuration Examples for Manually Configured IPv6 over IPv4 Tunnels
- Additional References
- Feature Information for Manually Configured IPv6 over IPv4 Tunnels
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.
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.
Information About Manually Configured IPv6 over IPv4 Tunnels
Overlay Tunnels for IPv6
Overlay tunneling encapsulates IPv6 packets in IPv4 packets for delivery across an IPv4 infrastructure (a core network or the figure below). By using overlay tunnels, you can communicate with isolated IPv6 networks without upgrading the IPv4 infrastructure between them. Overlay tunnels can be configured between border devices or between a border device and a host; however, both tunnel endpoints must support both the IPv4 and IPv6 protocol stacks. IPv6 supports the following types of overlay tunneling mechanisms:
Manual
Generic routing encapsulation (GRE)
IPv4-compatible
6to4
Intrasite Automatic Tunnel Addressing Protocol (ISATAP)
Note | Overlay tunnels reduce the maximum transmission unit (MTU) of an interface by 20 octets (assuming that the basic IPv4 packet header does not contain optional fields). A network that uses overlay tunnels is difficult to troubleshoot. Therefore, overlay tunnels that connect isolated IPv6 networks should not be considered a final IPv6 network architecture. The use of overlay tunnels should be considered as a transition technique toward a network that supports both the IPv4 and IPv6 protocol stacks or just the IPv6 protocol stack. |
Use the table below to help you determine which type of tunnel that you want to configure to carry IPv6 packets over an IPv4 network.
Tunneling Type |
Suggested Usage |
Usage Notes |
---|---|---|
Manual |
Simple point-to-point tunnels that can be used within a site or between sites. |
Can carry IPv6 packets only. |
GRE- and IPv4- compatible |
Simple point-to-point tunnels that can be used within a site or between sites. |
Can carry IPv6, Connectionless Network Service (CLNS), and many other types of packets. |
IPv4- compatible |
Point-to-multipoint tunnels. |
Uses the ::/96 prefix. We do not recommend using this tunnel type. |
6to4 |
Point-to-multipoint tunnels that can be used to connect isolated IPv6 sites. |
Sites use addresses from the 2002::/16 prefix. |
6RD |
IPv6 service is provided to customers over an IPv4 network by using encapsulation of IPv6 in IPv4. |
Prefixes can be from the SP’s own address block. |
ISATAP |
Point-to-multipoint tunnels that can be used to connect systems within a site. |
Sites can use any IPv6 unicast addresses. |
Individual tunnel types are discussed in detail in this document. We recommend that you review and understand the information about the specific tunnel type that you want to implement. When you are familiar with the type of tunnel you need, see the table below for a summary of the tunnel configuration parameters that you may find useful.
Tunneling Type |
Tunnel Configuration Parameter |
|||
---|---|---|---|---|
Tunnel Mode |
Tunnel Source |
Tunnel Destination |
Interface Prefix or Address |
|
Manual |
ipv6ip |
An IPv4 address, or a reference to an interface on which IPv4 is configured. |
An IPv4 address. |
An IPv6 address. |
GRE/IPv4 |
gre ip |
An IPv4 address. |
An IPv6 address. |
|
IPv4- compatible |
ipv6ip auto-tunnel |
Not required. These are all point-to-multipoint tunneling types. The IPv4 destination address is calculated, on a per-packet basis, from the IPv6 destination. |
Not required. The interface address is generated as ::tunnel-source/96. |
|
6to4 |
ipv6ip 6to4 |
An IPv6 address. The prefix must embed the tunnel source IPv4 address. |
||
6RD |
ipv6ip 6rd |
An IPv6 address. |
||
ISATAP |
ipv6ip isatap |
An IPv6 prefix in modified eui-64 format. The IPv6 address is generated from the prefix and the tunnel source IPv4 address. |
IPv6 Manually Configured Tunnels
A manually configured tunnel is equivalent to a permanent link between two IPv6 domains over an IPv4 backbone. The primary use is for stable connections that require regular secure communication between two edge devices or between an end system and an edge device, or for connection to remote IPv6 networks.
An IPv6 address is manually configured on a tunnel interface, and manually configured IPv4 addresses are assigned to the tunnel source and the tunnel destination. The host or device at each end of a configured tunnel must support both the IPv4 and IPv6 protocol stacks. Manually configured tunnels can be configured between border devices or between a border device and a host. Cisco Express Forwarding switching can be used for IPv6 manually configured tunnels, or Cisco Express Forwarding switching can be disabled if process switching is needed.
How to Enable Manually Configured IPv6 over IPv4 Tunnels
Configuring Manual IPv6 Tunnels
With manually configured IPv6 tunnels, an IPv6 address is configured on a tunnel interface, and manually configured IPv4 addresses are assigned to the tunnel source and the tunnel destination. The host or device at each end of a configured tunnel must support both the IPv4 and IPv6 protocol stacks.
1.
enable
2.
configure terminal
3.
interface tunnel
tunnel-number
4.
Enter one of the following commands:
5.
tunnel source {ip-address |
interface-type
interface-number}
6.
tunnel destination
ip-address
7.
tunnel mode ipv6ip
8.
end
DETAILED STEPS
Configuration Examples for Manually Configured IPv6 over IPv4 Tunnels
Example: Configuring Manual IPv6 Tunnels
The following example configures a manual IPv6 tunnel between router A and router B. In the example, tunnel interface 0 for both router A and router B is manually configured with a global IPv6 address. The tunnel source and destination addresses are also manually configured.
Router A Configuration
interface ethernet 0 ip address 192.168.99.1 255.255.255.0 interface tunnel 0 ipv6 address 3ffe:b00:c18:1::3/127 tunnel source ethernet 0 tunnel destination 192.168.30.1 tunnel mode ipv6ip
Router B Configuration
interface ethernet 0 ip address 192.168.30.1 255.255.255.0 interface tunnel 0 ipv6 address 3ffe:b00:c18:1::2/127 tunnel source ethernet 0 tunnel destination 192.168.99.1 tunnel mode ipv6ip
Example: IPv6 over GRE IPv4 Tunnel
Example: Configuring CE1
! ipv6 unicast-routing ipv6 cef ! interface Ethernet0/0 no ip address ipv6 address 2001:DB8:2:1::1/64 no shutdown exit ! ! ipv6 route 2001:DB8:2:2::/64 2001:DB8:2:1::2 ipv6 route 2001:DB8:2:4::/64 2001:DB8:2:1::2 !
Example: Configuring PE1
ipv6 unicast-routing ipv6 cef ! interface Tunnel0 no ip address ipv6 address 2001:DB8:2:4::1/64 tunnel source 10.22.22.22 tunnel destination 10.44.44.44 exit ! interface Ethernet0/0 no ip address ipv6 address 2001:DB8:2:1::2/64 no shutdown exit ! interface Ethernet1/1 no ip address ip address 10.22.22.22 255.255.255.0 no shutdown exit ! ip route 10.44.44.0 255.255.255.0 10.22.22.23 ipv6 route 2001:DB8:2:2::/64 Tunnel0 2001:DB8:2:4::2
Example: Configuring PE2
! ipv6 unicast-routing ipv6 cef ! interface Tunnel0 no ipv6 address ipv6 address 2001:DB8:2:4::2/64 tunnel source 10.44.44.44 tunnel destination 10.22.22.22 exit ! interface Ethernet0/0 no ipv6 address ipv6 address 2001:DB8:2:2::1/64 no shutdown exit ! interface Ethernet1/0 no ip address ip address 10.44.44.44 255.255.255.0 no shutdown exit ! ip route 10.22.22.0 255.255.255.0 10.44.44.43 ! ipv6 route 2001:DB8:2:1::/64 Tunnel0 2001:DB8:2:4::1 !
Example: Configuring CE2
! ipv6 unicast-routing ipv6 cef ! ! interface Ethernet0/0 no ipv6 address ipv6 address 2001:DB8:2:2::2/64 no shutdown exit ! ! ipv6 route 2001:DB8:2:1::/64 2001:DB8:2:2::1 ipv6 route 2001:DB8:2:4::/64 2001:DB8:2:2::1 !
Example: Configuring Device X
! interface Ethernet1/0 no ip address ip address 10.44.44.43 255.255.255.0 no shutdown exit ! interface Ethernet1/1 no ip address ip address 10.22.22.23 255.255.255.0 no shutdown exit !
Example: Verifying the Tunnel Configuration
From CE1
Device# ping ipv6 2001:db8:2:2::2 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 2001:DB8:2:2::2, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/9/43 ms Device# ping ipv6 2001:db8:2:2::2 source 2001:db8:2:1::1 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 2001:DB8:2:2::2, timeout is 2 seconds: Packet sent with a source address of 2001:DB8:2:1::1 !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms
From PE1
Device# show tunnel interface Tunnel0 Mode:GRE/IP, Destination 10.44.44.44, Source 10.22.22.22 IP transport: output interface Ethernet1/1 next hop 10.22.22.23 Application ID 1: unspecified Linestate - current up Internal linestate - current up, evaluated up Tunnel Source Flags: Local Transport IPv4 Header DF bit cleared OCE: IP tunnel decap Provider: interface Tu0, prot 47 Performs protocol check [47] Protocol Handler: GRE: opt 0x0 ptype: ipv4 [ipv4 dispatcher: punt] ptype: ipv6 [ipv6 dispatcher: from if Tu0] ptype: mpls [mpls dispatcher: drop] ptype: otv [mpls dispatcher: drop] ptype: generic [mpls dispatcher: drop] There are 0 tunnels running over the EON IP protocol There are 0 tunnels running over the IPinIP protocol There are 0 tunnels running over the NOSIP protocol There are 0 tunnels running over the IPv6inIP protocol There are 0 tunnels running over the RBSCP/IP protocol Device# show ip route 10.44.44.44 Routing entry for 10.44.44.0/24 Known via "static", distance 1, metric 0 Routing Descriptor Blocks: * 10.22.22.23 Route metric is 0, traffic share count is 1 Device# debug ipv6 icmp ICMP Packet debugging is on *Jan 1 10:57:37.882: ICMPv6: Sent R-Advert, Src=FE80::A8BB:CCFF:FE00:5200, Dst=FF02::1 *Jan 1 11:00:18.634: ICMPv6: Received R-Advert, Src=FE80::A8BB:CCFF:FE00:5200,Dst=FF02::1
Additional References
Related Documents
Related Topic |
Document Title |
---|---|
IPv6 addressing and connectivity |
IPv6 Configuration Guide |
Cisco IOS commands |
|
IPv6 commands |
|
Cisco IOS IPv6 features |
Standards and RFCs
Standard/RFC |
Title |
---|---|
RFCs for IPv6 |
IPv6 RFCs |
MIBs
MIB |
MIBs Link |
---|---|
|
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL: |
Technical Assistance
Description |
Link |
---|---|
The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password. |
Feature Information for Manually Configured IPv6 over 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.Feature Name |
Releases |
Feature Information |
---|---|---|
IPv6 Tunneling: Manually Configured IPv6 over IPv4 Tunnels |
Cisco IOS XE Release 2.1 |
A manually configured tunnel is equivalent to a permanent link between two IPv6 domains over an IPv4 backbone. The following commands were introduced or modified: tunnel destination, tunnel ipv6ip, tunnel source. |