I'm asking about the L2TP Secret Tab. I have no idea for what it is.Dont have a clue about what you are talking about. Maybe its a secret.
I do understand IPSEC secret aka on this link.
https://help.mikrotik.com/docs/display/ROS/L2TP
May you explain these acronyms?For using the Mikrotik as an LNS, annoyingly they never implemented the LAC functionality.