I have recently configured a VPN server hosted in AWS EC2. Details: Centos 6.4, openswan, xl2tpd, NAT-traversal. The configuration works great for a scenario when only one user connects form a given public IP address behind NAT. But when there are multiple clients behind same NAT, every new client connection drops old one. Looking at logs I can make a conclusion that l2tp treats all connections from the same nat as one.
Am I missing something? Is there a solution?
Your help is much appreciated.