What Are the Causes of the L2TP Dial-up Failure?

Latest reply: Jan 14, 2017 16:18:04 1173 1 0 0

What Are the Causes of the L2TP Dial-up Failure?

The causes of the L2TP dial-up failure are as follows:

  • The firewall deployed on the public network or the built-in firewall on the PC discards L2TP packets.
  • The corresponding L2TP port, usually UDP port 1701, is disabled or occupied. For example: ACL or NAT is configured on the port.
  • The user name and password configured on the LAC are incorrect, or no related user is configured on the LNS. Check whether the user password in the AAA view is set to cipher but not irreversible-cipher format.
  • The configuration address, such as the static address of the VT interface, is incorrect.
  • The tunnel authentication modes are different.
  • LCP renegotiation is not configured.
  • The address pool cannot meet user requirement or no address pool is configured.
  • No gateway address is reserved in the IP address pool, so that the gateway address is allocated to users.
  • The LAC and LNS have no reachable routes to each other.
  • An incorrect remote tunnel name is specified in the L2TP group view.
  • The authentication domain is incorrectly configured.
  • The control packets sent by the PC client do not carry the SQ number, so that the L2TP negotiation fails.
  • When IPSec encryption is used, the IPSec parameters on both ends are different.

  • x
  • convention:

Created Jan 14, 2017 16:18:04 Helpful(0) Helpful(0)

thank you
  • x
  • convention:


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