Tunnel remins down even after negotiation is initiated
From the debug L2tp infromation we can see the following error:
Local Tunnel Name: Tunnel ID:1
Remote Tunnel Name:XXX Tunnel ID:0
Try Times:1 Down Reason:1
Easiest way to handle this kind of issue is to debug L2TP and see exactly where the process fails.
After finding the cause of this issue the easiest solution is accept all tunnel names. for this you need to run the following command:
allow l2tp virtual-template 1 --> without specifing a remote name
The cause of this issue is the inconsistency between the locally configured and remote tunnel name.
When facing L2TP or IPSec issue best practice is to debug to see where the process fails.