Manual

Layer 2 Tunnel Protocol Version 3

Restrictions for Layer 2 Tunnel Protocol Version 3

Cisco IOS Releases 12.0(29)S and 12.2(25)S

• Enhanced 4-port synchronous serial port adapter

• 8-port synchronous serial port adapter

• Single-port HSSI adapter

• Dual-port HSSI adapter

• Single-port enhanced OC3 ATM port adapter

• 8-port multichannel E1 G.703/G.704 120-ohm interfaces

• 2-port multichannel E1 G.703/G.704 120-ohm interfaces

• 8-port multichannel T1 with integrated data service units (DSUs)

• 8-port multichannel T1 with integrated channel service units (CSUs) and DSUs

• 4-port multichannel T1 with integrated CSUs and DSUs

• 2-port multichannel T1 with integrated CSUs and DSUs

• 8-port multichannel T1/E1

• 1-port multichannel T3 interface

• 1-port multichannel E3 interface

• 2-port enhanced multichannel T3 port adapter

• Single-port T3 port adapter

• Single-port E3 port adapter

• 2-port T3 port adapter

• Single-port Packet over Sonet (PoS), single-mode, long reach

• Single-port PoS, single-mode, intermediate reach

• Single-port PoS, multimode

• Eight-port T1 ATM port adapter with Inverse multiplexing over ATM (IMA)

• Eight-port E1 ATM port adapter with IMA

L2TPv3 is supported on the following port adapters for the Cisco 7200 series routers only:

• 8-port Ethernet adapter

• 4-port Ethernet adapter

General L2TPv3 Restrictions

• CEF must be enabled for the L2TPv3 feature to function. The Xconnect configuration mode is

blocked until CEF is enabled. On distributed platforms, such as the Cisco 7500 series, if CEF is

disabled while a session is established, the session is torn down and remains down until CEF is

reenabled. To enable CEF, use the ip cef or ip cef distributed command.

• The IP local interface must be a loopback interface. Configuring any other interface with the ip local

interface command will result in a nonoperational setting.