In LNS and LAC equipment with L2TP configuration, LAC and LNS did not establish tunnel.
In the LNS side in L2TP debug information output, in the LAC side L2TP debug information output.
On the LAC side is added to the LNS server gateway routing tunnel can normally established.
First check that the ends of the profile, confirm that the configuration is correct and complete, according to LNS and LAC side debugging results, LNS side without debugging information output situation, may very well be the routing problem, or intermediate equipment packet filtering strategy intercepted L2TP packet, by examining the LAC side and LAC side routing configuration contrast the L2TP configuration information, found no yo configuration to the LNS server gateway routing.
In the L2TP configuration in LAC side need to configure two routes, one is to the LNS gateway routing, one is to end segment, due to the LNS gateway routing alone to the routing page to configure, often ignored, so need to check whether there is a route.