5.1. Tunnel Commands

Command Purpose

Use this command to create a new tunnel interface.

Use the no form of this command to destroy the tunnel interface.

Prerequisites

Command Syntax

interface tunnel TUNNEL-ID

no interface tunnel TUNNEL-ID

Command Mode

Global Config

Default

None

Usage

Before connect 2 IPv6 networks by an IPv4 network, a tunnel interface is required. The tunnel is available after set some attributes. After IPv6 is enabled the tunnel interface can forward IPv6 packets.

Examples

This example shows how to create a tunnel interface:

Switch# configure terminal
Switch(config)# interface tunnel 1

Related Commands

show interface tunnel

Command Purpose

Use this command to specify the IPv6 transition tunnel protocol.

Use the no form of this command to unset the tunnel protocol.

Prerequisites

Command Syntax

tunnel mode tunnel mode ( erspan ( ecmp-dst-gre | ) | gre | ipv6ip ) ( 6to4 | isatap | )

no tunnel mode

Command Mode

Interface Configuration

Default

None

Usage

This command specifies a tunnel encapsulation mode for IPv6 in IPv4. When the keywords “6to4” or “isatap” is not specified, then it is a manual tunnel. Tunnel mode is not allowed to change from 6to4 to ISATAP when 6to4 relay routes are configured. Users should unset the tunnel destination before change from manual tunnel to automatic tunnel.

Examples

This example shows how to create a 6to4 Tunnel:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel mode ipv6ip 6to4

Related Commands

tunnel source

tunnel destination

Command Purpose

Use this command to specify the tunnel source. Use the no form of this command to unset the tunnel source.

Prerequisites

Command Syntax

tunnel source ( IP_ADDR | IFNAME )

no tunnel source

Command Mode

Interface Configuration

Default

None

Usage

Every tunnel must have a tunnel source. If users specify the IFNAME format, system will choose the primary address as tunnel source.

Examples

This example shows how to set the tunnel source:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel source 3.3.3.3

Related Commands

tunnel mode ipv6ip

tunnel destination

Command Purpose

Use this command to specify a tunnel destination address in an IPv4 portion.

Use the no parameter to un-specify the address.

Prerequisites

Command Syntax

tunnel destination IP_ADDR

no tunnel destination

Command Mode

Interface Configuration

Default

None

Usage

Automatic tunnel such as 6to4 and ISATAP must not configure tunnel destination.

Examples

This example shows how to set the tunnel destination:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel destination 4.4.4.4

Related Commands

tunnel source

tunnel mode ipv6ip

Command Purpose

Use this command to enable tunnel decapsulation for interfaces. Use the form of this command to restore the default configuration.

Prerequisites

Command Syntax

tunnel ( enable | disable )

Command Mode

Interface Configuration

Default

By default, tunnel decapsulation is disabled on all interfaces.

Usage

None

Examples

This example shows how to enable tunnel decapsulation on interface eth-0-1:

Switch# configure terminal
Switch(config)# interface eth-0-1
Switch(config-if)# tunnel enable

Related Commands

interface

Command Purpose

Use this command to configure tunnel ECMP destinations IP address.

Use the form of this command to unset this configuration.

Prerequisites

Command Syntax

tunnel ecmp-destination IP_ADDR

no tunnel ecmp-destination IP_ADDR

Command Mode

Interface Configuration

Default

None

Usage

Automatic tunnel such as 6to4 and ISATAP must not configure tunnel destination (multi destination).

Examples

This example shows how to enable tunnel decapsulation on interface tunnel 1:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel ecmp-destination 1.1.1.1
Switch(config-if)# tunnel ecmp-destination 2.2.2.2

Related Commands

tunnel source

tunnel mode (ecmp-dst-gre | ) | gre)

Command Purpose

Use this command to configure the tunnel gre key value.

Use the form of this command to unset this configuration

Prerequisites

Command Syntax

tunnel gre key KEY_VALUE

no tunnel gre key

Command Mode

Interface Configuration

Default

None

Usage

Improve the security of the gre tunnel, configure the gre key to do the checkout of point to point.

Examples

This example shows how to enable tunnel decapsulation on interface tunnel 1:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel gre key 100

Related Commands

show running-config interface tunnel

Command Purpose

Before the mirror traffic passes through the tunnel, encapsulate the traffic with the extend header.

Use no the form of this command to unset this configuration.

Prerequisites

Command Syntax

tunnel extend-header

no tunnel extend-header

Command Mode

Interface Configuration

Default

None

Usage

• spanExtendHeaderCopyHash, using the new hash or not;

• PacketInfo.skipTimeInfoUpdate, fixed with 1;

• if spanExtendHeaderCopyHash is 1, the filed consist with hash (8 bit) and 0 (8 bit); if spanExtendHeaderCopyHash is 0, the filed consist with source port of the mirror (16 bit).

Without dst-load-balance parameter, spanExtendHeaderCopyHash will be 0, and extend-header field does not contain the hash value;

with dst-load-balance parameter, spanExtendHeaderCopyHash will be 1, and extend-header field contain the hash value.

Examples

This example shows how to enable extend-header hash for load balance:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel extend-header
Switch(config-if)# tunnel extend-header dst-load-balance

Related Commands

show running-config interface tunnel

Command Purpose

Use this command to configure the extend header id.

Use the no form of this command to unset this configuration.

Prerequisites

Command Syntax

tunnel extend-header id ID_VALUE

no tunnel extend-header id ID_VALUE

Command Mode

Interface Configuration

Default

0

Usage

None

Examples

This example shows how to enable tunnel decapsulation on interface tunnel 1:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel extend-header id 30

Related Commands

show running-config interface tunne

Command Purpose

Use this command to specify a value of Differentiated Services Code Point (DSCP) in the tunnel IPv4 encapsulation header.

Use the no parameter to inheriting the underlying physical interface value by default.

Prerequisites

Command Syntax

tunnel dscp DSCP

no tunnel dscp

Command Mode

Interface Configuration

Default

By default, the DSCP value is inherited from original IPv6 packet.

Usage

None

Examples

This example shows how to set the outer IPv4 header DSCP value as 40:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel dscp 40

Related Commands

interface

Command Purpose

Use this command to specify a value of time to live (TTL) in the tunnel IPv4 encapsulation header.

Use the no parameter to inheriting the underlying physical interface value by default.

Prerequisites

Command Syntax

tunnel ttl TTL

no tunnel TTL

Command Mode

Interface Configuration

Default

By default, the TTL value is inherited from original IPv6 packet.

Usage

None

Examples

This example shows how to set the outer IPv4 header TTL value as 254:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# tunnel ttl 254

Related Commands

interface

Command Purpose

Use this command to specify the Tunnel interface MTU.

Use the no form of this command to restore to the default value.

Prerequisites

Command Syntax

ipv6 mtu MTU

no ipv6 mtu

Command Mode

Interface Configuration

Default

1480

Usage

System does not support Path MTU Discovery on tunnel interface. This command is only allowed on tunnel interface.

Examples

This example sets the tunnel interface MTU to 1280:

Switch# configure terminal
Switch(config)# interface tunnel 1
Switch(config-if)# ipv6 mtu 1280

Related Commands

tunnel ttl

Command Purpose

Use this command to display the tunnel information.

Prerequisites

Command Syntax

show interface tunnel TUNNEL-ID

Command Mode

Privileged EXEC

Default

None

Usage

None

Examples

This example displays the tunnel information:

Switch# show interface tunnel1

Interface tunnel1
Interface current state: UP
Hardware is Tunnel
Index 8193 , Metric 1 , Encapsulation TUNNEL
VRF binding: not bound
Tunnel protocol/transport IPv6/IP, Status Valid
Tunnel source 1.1.1.1(eth-0-1), destination 2.2.2.2
Tunnel DSCP inherit, Tunnel TTL 64
Tunnel transport MTU 1480 bytes

Related Commands

show ipv6 interface tunnel

Command Purpose

Use this command to display the tunnel peers resource information.

Prerequisites

Command Syntax

show resource tunnel

Command Mode

Privileged EXEC

Default

None

Usage

None

Examples

This example displays the tunnel peers resource information:

Switch# show resource tunnel

Tunnel
Resource Used Capability
=============================================================
Peers 1 8

Related Commands

None