Something interesting about Hyper-V Networking...
Previously, I've mentioned that I've replaced my motherboard with Asus Rampage Formula. This board comes with a dual gigabit lan port. So I was playing with the network configuration on my hyper-v host. The LAN Left is where the virtual network switch is attached to, and all virtual machines uses this to communicate. The LAN Right is where the host is using to communicate.
I remember seeing a network layer diagram somewhere which I can't find now. It says that when network traffic comes into a network card, it will route the traffic to both the host and the virtual machine network switch, which means installing ISA on virtual machine does not protect the host. Installing IS on host does not protect the virtual machines if they are listening to the external network card.
Since I now have a dedicated lan port for the host, I was playful, and disabled the LAN port for virtual machines on my host. If I do that on virtual server / virtual pc, I'm quite sure that the network connectivity will be gone, even though the network cable is still shown as attached. But in Hyper-V, it is still working! I can access my virtual machines from my laptop, and vice versa. In fact, if i disable both, I still have network connectivity to my virtual machines, though I won't be able to access the host!
Now, if I virtualise ISA, since the virtual network switch does not have an IP, and the external network card does not have an IP for the host, does it mean that all network will go through ISA? Does it means that my ISA really behaves exactly like a physical box, without compromising the host?
Cool huh?
[Updated]
Found something that explain how networking works in hyper-v