Issue Description
Topology: PC------LAC(R vendor) ------LNS(R2600);
Failure descriptions: PC can dial in normal, but it cannot dial in after a while.
Alarm Information
The debug is switched on when the user is dialing, and the fault prompt as L2TP::Error::receive invalid AVP in ICCN is found.
Handling Process
In l2tp-group, add the mandatory authentication of mandatory-lcp and the problem is solved.
For example:
l2tp-group 1
Default L2TP group
allow l2tp virtual-template 1
mandatory-lcp
tunnel password simple XXXX
Root Cause
According to debug information, we can find that the tunnel has set up normally, but it fails to negotiate with LAC.
Suggestions
At the beginning, configure mandatory-lcp.