I am working with a IIGS connected to A2SERVER using the supplied VM. Thanks to GeoffB I got localtalk working through a Farallon PN848 and Marinetti. MacIP connects but does not actually communicate.
I found some older code for MacGate and have managed to update the code to the point that it compiles cleanly and runs in the VM (Ubuntu with kernel 3.5.0). MacGate is supposed to be an appletalk to TCP/IP gateway and/or router.
The IIGS connects to the network and finds the gateway using MacIP with Marinetti 3.X installed. However, this is currently the extent of my success with this and neither Telnet nor Casper work.
If anyone is interested in helping out with this, please see https://sourceforge.net/p/macgated/code/ci/master/tree/.
Currently, if configured to do so, the software will scan for existing ip addrs on startup and add routes. It does not actually allow communication back to the connected client, nor does it listen properly for new clients.
Using wireshark, I can see the DDP request, the TCP request as decoded by the ipddp kernel module, as well as the TCP response.