I have a CentOS VM sitting on HyperV host with two interfaces, One interface connected to the domain Network via a switch (192.168.1.8 /24) GW 192.168.1.254. Another interface is connected directly to the firewall (fortigate) (172.20.0.1/29) GW 172.20.0.254.The above interfaces are also setup as Hyper-V Virtual switches on the Host.
The Gateways are interfaces setup on the FW setup to segregate traffic.
172.20.0.x /29 is public address segment assigned by the ISP.
The guest VM has two interfaces eth0 (192.168.1.7/24) connected via 192.168.1.8 (Virtual Switch) on host. And eth1(126.96.36.199/29) connected via 172.20.0.1 (Virtual Switch) on host.
Problem is I can ping both interfaces on the VM from the Host and from the Firewall. But I can not ping eth1(172.20.0.2) from the internet, but able to reach host interface 172.20.0.1 from the internet.
Please note that CentOS Guest VM can ping Local Area Networks resources and reach internet with source ping from both interfaces.
When I trace route to both addresses 172.20.0.1 and 172.20.0.2 from an external source IP on AWS. I can reach 172.20.0.1 (Host Interface). Route to 172.20.0.2 (VM Interface) terminates just before the firewall from outside.
My train of thought is now leading me to think that there is additional configuration that needs to be done on the FW, maybe add a static route on the FW relaying traffic directly to the VM? Any thoughts? I just want to be sure before I commence with this exercise.