[comp.unix.ultrix] DecNet-Ultrix / TCP-IP incompatability?

kocks@jessica.Stanford.EDU (Peter Kocks) (02/24/90)

Help.   I have two dec3100s running ultrix.  One is a client of the
other and they communicate via TCP/IP protocols.  I recently installed
DecNet-Ultrix and found that the server no longer responded to NFS
requests from the client.  My installation of DecNet was incomplete,
i.e. I did not configure the nodes.  

Why does DecNet mess up the NFS file serving?  Do I have to setup the
NFS server to serve using DecNet protocols instead of standard TCP/IP
protocols?   If so why.  What am I doing wrong?

Thanks.

Peter Kocks
kocks@jessica.Stanford.EDU

michaud@decvax.dec.com (Jeff Michaud) (02/24/90)

> Help.   I have two dec3100s running ultrix.  One is a client of the
> other and they communicate via TCP/IP protocols.  I recently installed
> DecNet-Ultrix and found that the server no longer responded to NFS
> requests from the client.  My installation of DecNet was incomplete,
> i.e. I did not configure the nodes.  

	DECnet, when it is turned on, changes the hardware address on
	the ethernet device.  The other TCP systems however that your
	system was/are talking to however have the old ethernet address
	in their arp caches.

	DECnet does issue the ioctl to send out an arp delete request
	when it starts up.  Maybe in this case the client didn't
	see the arp message.  The arp entry in the clients cache should
	time out anyways I believe.  You can also do a manual "arp -d ..."
	on the client to remove it from the cache.

/--------------------------------------------------------------\
|Jeff Michaud    michaud@decwrl.dec.com  michaud@decvax.dec.com|
|DECnet-ULTRIX   #include <standard/disclaimer.h>              |
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meggers@orion.oac.uci.edu (mark eggers) (02/24/90)

Actually, the easiest thing to do is start up DECnet-Ultrix first, and then
start up the TCP/IP stuff. DECnet changes your Ethernet hardware address
(sigh - what a stupid thing to do), but then IP starts up and uses the
new Ethernet hardware address.

For other machines - either wait until the ARP cache times out or do an
arp -d hostname (superuser privledges) to remove the improper address.

/mde/

barmar@think.com (Barry Margolin) (02/26/90)

In article <JV.90Feb25231631@mhres.mh.nl> jv@mh.nl (Johan Vromans) writes:
>Does anyone know why DECnet changes the hardware address?

I believe DECnet uses a simple formula to translate from DECnet addresses
to Ethernet addresses, rather than a dynamic mechanism like ARP.
Therefore, it must set your Ethernet address to be the one that
corresponds to your DECnet address.
--
Barry Margolin, Thinking Machines Corp.

barmar@think.com
{uunet,harvard}!think!barmar

jv@mh.nl (Johan Vromans) (02/26/90)

In article <25E5C914.26964@orion.oac.uci.edu> meggers@orion.oac.uci.edu (mark eggers) writes:

: DECnet changes your Ethernet hardware address (sigh - what a
: stupid thing to do), but then IP starts up and uses the new Ethernet
: hardware address.

Does anyone know why DECnet changes the hardware address?

Johan
--
Johan Vromans				       jv@mh.nl via internet backbones
Multihouse Automatisering bv		       uucp: ..!{uunet,hp4nl}!mh.nl!jv
Doesburgweg 7, 2803 PL Gouda, The Netherlands  phone/fax: +31 1820 62944/62500
------------------------ "Arms are made for hugging" -------------------------

michaud@decvax.dec.com (Jeff Michaud) (02/27/90)

> >Does anyone know why DECnet changes the hardware address?
> I believe DECnet uses a simple formula to translate from DECnet addresses
> to Ethernet addresses, rather than a dynamic mechanism like ARP.
> Therefore, it must set your Ethernet address to be the one that
> corresponds to your DECnet address.

	Correct.  However, in Phase V this is fixed as we go
	to OSI addressing.  See the DNA Phase V General Description
	for more info.

/--------------------------------------------------------------\
|Jeff Michaud    michaud@decwrl.dec.com  michaud@decvax.dec.com|
|DECnet-ULTRIX   #include <standard/disclaimer.h>              |
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