[Info-vax] SOLVED: Re: tcpip gateway question

[glen herrmannsfeldt]

Richard B. Gilbert <rgilbert88 at comcast.net> wrote:
 
< I'm not certain but I suspect that your problem is due to the fact that 
< DECnet sets the Ethernet address to AA-00-04-00-FB-04.  If you start 
< TCP/IP first, it will get the original hardware address for the 
< interface.  When DECnet starts it will set the address to the DECnet 
< node address and leave TCP/IP swinging in the breeze!

That should only happen until the ARP cache is updated.  Any host
that tries to connect after the MAC address change will get the
new address from ARP.  Most will update on the broadcast ARP reply,
but maybe not all.

I added comp.protocols.tcp-ip to this follow-up.  The question,
then, is what should happen when a host changes its MAC address?
(Specifically, for other hosts with the old address in ARP cache.)
 
< So start DECnet first and then TCP/IP.  Alternatively, you can decide 
< not to start DECnet at all.  Don't change your mind in mid stream!  If 
< you start TCP/IP and then DECnet, DECnet will change the Ethernet 
< address and screw up TCP/IP!!

That sounds like a fine solution.

-- glen