[HECnet] Need help with DECnet routing

[Marc Chametzky]

You have two (well, three) potential problems here.

Of the problems you list, most of them aren't actually the kinds of problems you'd expect. ESXi is very good about presenting multiple virtual interfaces to its guest operating systems over a single physical interface. ESXi creates a virtual bridge to handle this. It's even possible using VLANs to set up different LAN segments to isolate traffic between guests.

In this case, the Windows and the Linux system can see each other on the same LAN segment just fine. ESXi takes care of that very well.

I'm able to configure the two VMS systems' hardware address to reflect their DECnet-computed addresses, so that's not an issue.

Third - is the actual machine running windows, or did I misunderstand something?

The guest OS that's running the Alpha is Windows XP. I don't know what games Personal Alpha plays to make its networking work, but it's conceivable that there's some sort of issue there. I've dedicated the Windows network adapter to Personal Alpha's protocol interface, so Personal Alpha gets exclusive access to it. (This Windows system doesn't need TCP/IP connectivity anywhere... that makes it more secure anyway.)

There are two potential failure points that I can imagine. One is ESXi. I don't think that this is the problem since DUSTY (on the Linux guest) is able to see LULU's packets and establish adjacency. ESXi is at least passing those packets in one direction, so it should be able to do it in both.

The other potential point is in Windows, and perhaps Personal Alpha's network interface. It may be dropping packets it doesn't recognize, so DECnet routing packets don't make it. Maybe. When I get a chance to use Wireshark, I'll at least see what's going on from Windows' perspective.

--Marc


Windows have a very weird and appearantely unreliable
interface for programs that want to talk raw ethernet.
And for virtual machines, you do want to talk raw ethernet.
But these are all just potential problems. To really diagnose all of this, you'd have to be physically by the machine to test various things.
Depending on system, as well as virtual machine, these problems can be solved, but I wouldn't bet money on anything here. :-)
      Johnny