[comp.dcom.sys.cisco] Internet Problems

gaspar@STL-08SIMA.ARMY.MIL (Al Gaspar) (11/29/90)

	I'm not sure that this actually belongs in this group, but, since
we have an cisco AGS gateway, it seemed a good place to start.

	For some time now (a couple of years), we have had an AGS gateway
with one ethernet board (our software is currently at 8.1(19)).  It's
Internet address is 192.35.148.1.  Off of this gateway we have some
Unisys 5000/95s running SysV.3 from Unisys, a Vax 780 (on its way out)
running 4.3 bsd from mt. xinu, and some Sun products running 4.03
SunOs.  These machines are all set up to let the AGS handle their
routing.  These machines have generally good connectivity to the
ethernet (though the bsd and SunOs software seems a bit more reliable
than NET-5000 on the Unisys machines).

	Recently we added another ethernet board to our AGS gateway.  Its
address is 192.70.191.1.  Off of this ethernet we have hung two
SPARCstation 1+s running SunOs 4.1 (192.70.191.2 & 3) and one cisco
STS-10X terminal server (192.70.191.4).  These machines are also set
up to let the AGS handle their routing.  However, these machines
cannot reach and cannot be reached (using ping and traceroute) by any
machines outside of the milnet.  The only exception that I have found
to this is that I can (very) occasionally reach jpl-devvax.jpl.nasa.gov
(128.149.1.143) and a couple of the other machines 128.149.1.xxx
machines.  However, when I can reach these machines, traceroute
shows the addresses up to and including the milnet gateway at
moffett.mt.ddn.mil (26.0.0.16); after that it shows all *'s until it
hits the destination machine.  If I run traceroute off the AGS itself,
I get addresses all the way.

	The Defense Communications Agency (DCA) has told us that this
may be the result of some flaky mail gateways on the NSFNET maintained
by BBN.  The explanation given is that when these gateways hickup they
destroy all of the dynamic routing to the milnet and, therefore, only
those sites that are in static tables can reach outside of the
milnet and vice versa.  Since our first ethernet address has been
around awhile it presumably is in many static tables.  DCA also
tells us that BBN knows of the problem, but that a fix has a very low
priority.  I am wondering whether this explanation sounds plausible.
Are there any other possibilities that I might explore?  Any help or
suggestions will be greatly appreciated.  The current situation is
a pain...

Thanks--

Al

-- 
Al Gaspar	<gaspar@stl-08sima.army.mil>
USAMC SIMA, ATTN:  AMXSI-TTC, 1222 Spruce St., St. Louis, MO  63103-2834
COMMERCIAL:  (314) 331-4354	AUTOVON:  555-4354
uunet.uu.net!stl-08sima.army.mil!gaspar

fair@apple.com (Your Friendly Postmaster) (11/29/90)

The DDN management bulletin had a notice about this recently.
Basically, if you're on MILNET, you're hosed. I was once a MILNET
liaison at LLNL in 1986; I doubt much has changed since then...

	Erik E. Fair	apple!fair	fair@apple.com

long@nic.near.net (Daniel Long) (11/30/90)

	From: Al Gaspar <gaspar@stl-08sima.army.mil>
	Subject: Internet Problems
	Date: Wed, 28 Nov 90 08:45:20 CST

		I'm not sure that this actually belongs in this group, but, since
	we have an cisco AGS gateway, it seemed a good place to start.

Probably the tcp-ip@nic.ddn.mil would be a good place for this kind of
question.

		Recently we added another ethernet board to our AGS gateway.
	Its address is 192.70.191.1.  Off of this ethernet we have hung two
	SPARCstation 1+s running SunOs 4.1 (192.70.191.2 & 3) and one cisco
	STS-10X terminal server (192.70.191.4).  These machines are also set up
	to let the AGS handle their routing.  However, these machines cannot
	reach and cannot be reached (using ping and traceroute) by any machines
	outside of the milnet.  The only exception that I have found to this is
	that I can (very) occasionally reach jpl-devvax.jpl.nasa.gov
	(128.149.1.143) and a couple of the other machines 128.149.1.xxx
	machines.  However, when I can reach these machines, traceroute shows
	the addresses up to and including the milnet gateway at
	moffett.mt.ddn.mil (26.0.0.16); after that it shows all *'s until it
	hits the destination machine.  If I run traceroute off the AGS itself,
	I get addresses all the way.

The trick here is that NSFNET keeps a database of networks it knows about.
Your old network (192.35.148) is in that database.  Your new network is not.
You need to fill out an Internet Number Template available from NIC.DDN.MIL as
file: NETINFO:INTERNET-NUMBER-TEMPLATE.TXT.  In this template, question 4 
asks whether you want your network to be advertised to NSFNET (i.e. added to
the NSFNET database).  Contact HOSTMASTER@NIC.DDN.MIL for more information.

		The Defense Communications Agency (DCA) has told us that this
	may be the result of some flaky mail gateways on the NSFNET maintained
	by BBN.  The explanation given is that when these gateways hickup they
	destroy all of the dynamic routing to the milnet and, therefore, only
	those sites that are in static tables can reach outside of the milnet
	and vice versa.  Since our first ethernet address has been around
	awhile it presumably is in many static tables.  DCA also tells us that
	BBN knows of the problem, but that a fix has a very low priority.  I am
	wondering whether this explanation sounds plausible.  Are there any
	other possibilities that I might explore?  Any help or suggestions will
	be greatly appreciated.  The current situation is a pain...

I'm not an expert on the BBN Mailbridges which connect the MILNET to NSFNET
(and other networks) but I'll pass your note along to those who are.  However,
I'm quite sure that the problem you're experiencing with your new network has
nothing to do with the Mailbridges.

Hope this helps,
Dan 

medin@nsipo.nasa.gov (NASA ARC NSI Project Office) (11/30/90)

Well, not quite.  This is an acute problem, but various solutions are
being worked on.  We have one of the 2 FIX sites, and the MB here is
very busy, but it is a lot more efficient than it used to be. 
Unfortunately, the load has also greatly increased.  

There is going to be a get together on this problem at IETF next week.
We should know more then.  Understand however, that there are something
like 2000 nets floating around these days.  Figure out how large an
EGP NR message has to be to send these, then figure out how many of
these can flow over a 56 Kb line, where the updates are going off
every 2 minutes.  This is a matter of physics.  You need to change the
problem in order to accomodate this all on a 56Kbps based network.

						Thanks,
						   Milo