147
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8
Symptom
▶
Cause
▶
Remedy
L2TP/IPsec
connection or VPN
connection cannot
be established.
The service of L2TP/IPsec is not
enabled.
Enable the service of L2TP/IPsec (Configure
as “l2tp service on”.).
The IPsec setting is not correct.
• Check if the pre-shared key of IPsec is
correct.
• Check the type of tunnel interface (tunnel
encapsulation l2tp).
The PPP setting is not correct.
• Check if the ID and password for the PPP
authentication are correct.
• Check that the tunnel interface is bound
in the PP interface (pp bind tunnel1).
The terminal setting is not correct.
• Check if the destination address and the
host name are correct.
• Check if the pre-shared key of IPsec is
correct.
• Check if the user ID and password for
PPP authentication are correct. If user ID
or password is not correct, change to the
correct one.
• For the configuration of the terminal, refer
to the manual of the terminal.
Communication with the
destination cannot be established.
Execute the ping command to the destination
IP address, and check whether a response
is returned.
If no response is returned, check whether
communication is enabled in the destination
device.
L2TP/IPsec
connection is
disconnected
immediately.
The signal quality of the terminal
is poor.
Check the signal quality of the terminal, and
move to a place where signal quality is good.
The disconnection timer of L2TP/
IPsec is set.
Set the disconnection timer of L2TP/IPsec
to an appropriate time.
The keep alive setting of L2TP/
IPsec is inappropriate.
Set the interval and count of the keep alive
of L2TP/IPsec to an appropriate value.
In places with poor signal quality, the
response of keep alive may be lost
temporarily.
