3Com Switch 8800 Family IPsec Module Configuration and Command reference Guide

LAC Configuration 109
By default, L2TP is disabled.
Creating L2TP Group L2TP group needs to be created in order to fulfill related parameter configurations
of L2TP. It allows you not only to configure L2TP functions as needed but also to
implement one-to-one and one-to-many networking applications between LAC
and LNS. L2TP groups are numbered separately on LAC and LNS, so LAC and LNS
only need to keep consistent in the configurations of the involved L2TP groups
(e.g. remote name of Tunnel, start L2TP and LNS address, etc.).
These configurations are compulsory on LAC side.
Perform the following configuration in system view.
After a L2TP group is created, other configurations related to the L2TP group can
be performed in L2TP group view, for example, name of peer end, condition
triggering L2TP Tunnel setup request and LNS address.
By default, no L2TP group is created.
Setting Condition
Triggering L2TP Tunnel
Setup Request and LNS
Address
A security gateway will not send L2TP Tunnel setup request to some other devices
unless certain conditions are met. By configuring decision making rule based on
user information and specifying IP address of LNS, you may allow the security
gateway to determine whether a user is a VPN user and initiate connection with
the LNS. Up to five LNS addresses can be configured, meaning LNS backup is
allowed. In normal operations, local security gateway (LAC) sends Tunnel setup
request to the peer end (LNS) in the order in which LNS addresses are configured
until some LNS accepts the request. This LNS becomes the peer end of L2TP
Tunnel. An L2TP Tunnel setup request can be triggered by full user name and
domain name.
Perform the following configuration in L2TP group view.
The parameters above have no default values and they can be configured as
needed. But at least one triggering condition must be configured for initiating
L2TP Tunnel setup request.
When the L2TP LAC starts a L2TP Tunnel connection, the system checks whether
the L2TP group specified according to the complete user name exists. If the system
Tab le 85 Create/delete L2TP group
Operation Command
Create L2TP group l2tp-group group-number
Delete L2TP group undo l2tp-group group-number
Tab le 86 Set condition triggering L2TP Tunnel setup request and LNS address
Operation Command
Configure to check if the user is VPN
user and set IP address of LNS
start l2tp { ip ip-addr [ ip ip-addr] [ ip ip-addr] ... } {
domain domain-name | fullusername user-name }
Cancel the Tunnel setup request
configuration
undo start