NT and Linux box nextwork!

Are the machines connected back to back? Do you have a router?

1) Check the netmask on both systems.  In your case above, it should be 255.255.255.0.  

2) On the linux box make sure the default route is to the ethernet adapter.

3) On the NT box make sure that the TCP/IP configuration does not have packet filtering on.

4) Make sure that each machine can ping itself.  That is, can the NT box ping 192.168.0.2 and the linux box ping 192.168.0.1.

5) Make sure that your network physical connection is good.  You didn't mention whether it was 10Base-T, coax, other...  You may have a bad cable, hub, connector.  You may even have a faulty network adapter.

Okay.  The network is a coax back to back, properly terminated.  I see the Linux box TCPDUMP that the NT system seems to have a problem READING arp replies.  It sends out arp replies, but gets no answer.  It does not reply to ping.  The problem is *definately* on the end of the NT machine.  I've tried installing windows 98, windows 95.  Same problem all over.  

Everything you said is set up.  I seriously suspect that the windows ARP stuff is messed up.  Is there any way to replace the windows ARP system with another freeware / shareware package?  

I am becoming pretty desperate ;)

JHANCE: I was not given the answer I needed.  Please feel free to answer again.  I have increased the points to 800.  

I will give ANYONE an A who can help!  Please!  This is a VERY major problem for me.  If your solution works, you WILL get an A!

I must assume that the problem is not in Windows ARP in general as many people (including me) use Linux and NT on the same network every day without problems.  So the answer must lie in either your particular hardware or software setup.  Is it possible that the network card you are using on the NT side is faulty.  For example, if the IRQ line is bad (either on the card or the motherboard) you won't get received packets.  The fact that you get the same bad behavior with NT, 95, and 98 really leads me to believe that this is a hardware problem.

Yes.  I was wondering about that.  It can send but not receive apparently.  I run a 200 machine mixed network at work, consisting of 95, NT, linux, FreeBSD, sunos.  I've never ran into a problem like this though.  Let me try moving the card to another IRQ and see if that makes a difference.

This makes no sense!  I am seeing a LOT of netbios requests from the winNT machine to 192.168.0.255

I doubt its the card.  It has worked fine in the past with 10baseT, with the same two machines.  I was using a crossover cable.  However, that was 2 machines running windows 95 / NT.  

My question is is there a way to edit the ARP tables?  I have a feeling routing may be screwed up.

Here is what I get from route.  Note that I am also connected to the net via a modem (199.179.44.* stuff is the modem)

I think somewhere software is not configured properly.

Active Routes:

  Network Address          Netmask  Gateway Address        Interface  Metric
          0.0.0.0          0.0.0.0    199.179.44.40    199.179.44.40       1
        127.0.0.0        255.0.0.0        127.0.0.1        127.0.0.1       1
      192.168.1.0    255.255.255.0      192.168.1.2      192.168.1.2       2
      192.168.1.2  255.255.255.255        127.0.0.1        127.0.0.1       1
    192.168.1.255  255.255.255.255      192.168.1.2      192.168.1.2       1
     199.179.44.0    255.255.255.0    199.179.44.40    199.179.44.40       1
    199.179.44.40  255.255.255.255        127.0.0.1        127.0.0.1       1
   199.179.44.255  255.255.255.255    199.179.44.40    199.179.44.40       1
        224.0.0.0        224.0.0.0    199.179.44.40    199.179.44.40       1
        224.0.0.0        224.0.0.0      192.168.1.2      192.168.1.2       1
  255.255.255.255  255.255.255.255      192.168.1.2      192.168.1.2       1

I am unable to add the hardware address of the Linux box to win NT when I do
arp -s 192.168.0.1 <hardware address>

It just gives me the prompt back, and when I do arp -a it does not show it.  I still say that its some incompatibility with arp.

Suggestions? Ideas?

.1 isnt a valid IP.. it might very well be reserved.. have you tried using any other ip (0, 1, 127, 128, 255 are to be avoided at all cost)

(and 255 is the broadcast adress, so massive netbios traffice there is normal)

Absolutly nothing wrong in .1 or .2 with the Netmask of 255.255.255.0. The network is 192.168.0.0 and the broadcast is
192.168.0.255

As others have pointed out ARP is not working between these 2 machines. The thing about arp it that it is possible to test it unidirectionally.

I will assume that the Linux box works with other machines (if
there are only 2 then you need to borrow a third!). We can see
the broadcasts from the NT box so we know the NT machine can
send!

Ping from the NT machine to the Linux box.
   It fails but Look at the Linux box arp cache (arp -a)
   Does the IP address and Mac address of the NT box appear?

If yes then transmission from the NT box to the Linux system
occours correctly.

Clear the arp caches on both ends and then ping from the Linux
machine to the NT system. Look in the arp cache on the NT machine. (Same command.)

This should tell us in which way traffic is flowing - in fact
the suspision is that the NT machine is Deaf and not responding
to packets on the Ethernet interface so we will not get an entry
in the NT systems arp cache until we do we won't get ping to work.

With networking cards in PC's I have often found that cards are
either Dumb or Deaf. If Dumb then the IO address is normally the
base of the conflict. If Deaf then the IRQ is conflicting. Of course that assumes that the SMC card to card test works. With
SMC cards under Win 3.1 you also had to make sure that the Mapped
memory address was correct.

In this case we have NT. Is the PC a PCI based system and which
model SMC - if you use the drivers that come with NT on some Network cards from SMC they do not work correctly - try the ones
from the SMC Driver Disks. In fact never trust the hardware wizards selection of drivers for SMC cards in WIN95 or NT and always use the right driver disk for the card. Also If the PC is a PCI m/b and the card is ISA then you will need to set the IRQ in the BIOS - I prefer 5 or 10 and always avoid 2 or 3. PCI bus is edge triggered and ISA
is level triggered - you have to tell the bios which you are using ISA cards on for that reason.

It appears that the Windows machine will not ANSWER to ANY replies, whether ping or arp, nor READ any replies which are arp-related.  Both are SMC Ultra 16 cards.

TCPDUMP shows that Windows sends out arp requests, but never reads the replies.  

I attempted to buy a used network card, it ended up being an NE1000 and did not want to work at all.  I will try to purchase a new card today.

I have tried different IP's as well.
Thanks a lot!

This is very interesting.  I never accepted the answer :>
Oh well, there go my 850 points