[Simh] SimH networking on Ubuntu (dapper)

[Edward Berry]

Mark Pizzolato - Info Comm wrote:
> Let's go back to the simplest case which is with  2 NIC cards.
>
> What you need to do in this case is:
> 1) The primary NIC (eth0) will be setup normally and you should be able
> to ping and otherwise access nodes on the LAN.
> 2) The second NIC should be plugged into the SAME network as the primary
> NIC.
> 3) The second NIC SHOULD NOT be used by the networking on the Ubuntu
> system (i.e. NO IP Address explicitly assigned and none set by DHCP).
> You should have to explicitly turn on that NIC with something like
> "/sbin/ifconfig eth2 up"

I'm also interested in these instructions. On the ubuntu host,
is there a file /etc/sysconfig/network-scripts/ifcfg-eth2 ?
(I think there must be or ifup will fail (configuration for eth2 not found).
Does it have "PROTOCOL STATIC"? and no IP address or netmask?

I'm using a (now very old) simh vax, sharing the NIC with the linux host,
When the vax starts it puts the NIC in promiscuous mode so so it can receive
packets at the vax's IP, but of course in linux the NIC is configured
with the linux box's IP. So it may not matter if a static IP is assigned
to the vax-dedicated nic in linux (it just won't be used).

>   You can avoid the need to run the SIMH vax as root by leveraging Linux
> "Filesystem Capabilities" to give the SIMH vax executable the needed
> capabilities.

(maybe a dumb question from security point of view):
Why not run the vax console as root, then telnet in as a regular user
to do work. When you need to do SYSOPER stuff like mounting tapes or
disks, switch back to the console to do it.
Starting the vax from inside the linux "screen" command lets you put
away the console and resume it later, and only users logged in as root
will be able to resume the root's screen console.