User`s guide

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When checked, this checkbox causes the router to NOT actively attempt to establish an
L2TP tunnel. In this mode it will only use L2TP if the remote host requests it. When
unchecked, the router will actively try to establish an L2TP connection with the remote host.
Enable Server mode
When checked, this checkbox causes the router to act as a L2TP server.
Initiate connections to a.b.c.d
The value in this text box specifies the IP address of the remote host, i.e. the device that
will terminate the L2TP connection.
Use a.b.c.d as a backup
It is possible to specify a backup remote L2TP host server using this parameter. The text
box contains the IP address of the remote server to use.
Bring this tunnel up All the time/On demand
This parameter only applies to tunnels initiated from this router.
Bring this tunnel down if it is idle for h hrs, m mins, s secs
These radio buttons select whether or not the tunnel is permanently available or not. When
set to On demand, the tunnel will not activate automatically but will wait until it is
triggered by PPP. When set to On demand the values in the text boxes determine the
timeout after which the L2TP tunnel will closed down after the last L2TP call on that tunnel.
L2TP Window Size
The L2TP window size is selected from this drop down list. Available values are from 1 to 7.
Route UDP packets over interface x,y
These two text boxes specify the interface and its instance number that should be used for
L2TP UDP sockets. Specifying these parameters allow the router to raise the interface
should it be disconnected.
Source Port Normal/Variable
These radio buttons select the source port for the L2TP tunnel. When set to Normal the
default port number of 1701 is used. When set to Variable a random source port value will
be used.
Name
The value in this text box is the name that is used to identify the router during the
negotiation phase when establishing an L2TP tunnel.
Authentication Off/Secret
The radio buttons select whether or not to use authentication. This is normally set to Off as
most host systems require that IPsec be used over L2TP tunnels. If Authentication is set to
On, authentication is enabled and the Secret parameter becomes relevant. The value in the
text box contains a passphrase that is shared with the host and which will be used if the
remote host requests authentication and Authentication is set to Off here.
Related CLI Commands
Entity
Instance
Parameter
Values
Equivalent Web Parameter
l2tp n listen OFF,ON Act as a listener only
l2tp n swap_io OFF,ON Enable server mode
l2tp n remhost
Valid IP address
a.b.c.d
Initiate connections to a.b.c.d
l2tp n backremhost
Valid IP address
Use a.b.c.d as a backup