>I feel like this should be incredibly basic, and most people seem to be only having trouble with bridged networking.
>A traceroute from the host to the guest seems to indicate that the host doesn't even know about the vmware nat because it tries to go to the outside world.
It's incredibly basic and a limitation by the design of NAT. The same is true for bridged networking over Apple Internet Connection sharing (Apple NAT). I suggest reading the Drawbacks[/b] section and looking at the restricted and and port-restricted designs of NAT at http://en.wikipedia.org/wiki/Network_address_translation
There are other modes of VMware networking such as host-only that overlay logical networks which isolate the guest like NAT but allow pinging the guest from the host. Host-only networking is currently not available in this beta release of Fusion.
From the release notes
hardware TCP and UDP checksum offload, any TCP or UDP communication betwen the host and the
guest will fail when the guest is configured to use a bridged network adapter.
If you need communication between the Mac OS X host and the guest, you can either set up port
forwarding by editing /Libraries/Application Support/VMware Fusion/nat.conf and connect to the
forwarded port on the Mac OS host (for host-to-guest communication), or use the real IP address of the
host (for example, associated with "en0") from the guest (for guest-to-host communication).[/i]
I was unable to get this hint to work (the part about editing nat.conf) -- admittedly, their instructions are a bit vague, but I thought I could figure it out...but no go. When I'm running in NAT mode, the guest's IP address is 192.168.84.131, and it says my host's address is ...84.2, but on the host, I don't see this network at all, so I have no idea how the port forwarding is supposed to work.