I'm trying to move a site-to-site IPsec tunnel from a Cisco ASA 5505 and a BIG-IP LTM+AFM version 12.1.0. The tunnel was up and traffic flowed properly when the tunnel was terminated on ASA but not any longer. I have configured IKE phase 1 and IPsec phase 2 and traffic selectors with same parameters that were configured on the ASA and I have also configured a forwardning virtual server but my BIG-IP seems to drop ISAKMP traffic, it answers back to the peer with ICMP port 500 unreachable. What can be wrong? Am I missing something in Network Firewall? I have added ESP and ISAKMP to the Global rule and I can see Count increasing. But phase 1 doesn't work anyway.
Best regards, Andreas