The router is reporting a duplicate IP address and that could truly be
the cause of the problem.  So start going from PC to PC, but I  think
PC's running MS TCP/IP stack will get a blue screen if they try to
come up with an address that's already assigned.  So the problem could
be another piece of equipment on the LAN that comes up after a PC with
the same address.  However, I've seen this problem was when a HUB or
HUB connection went bonkers.  I've also had mysterious problems with
old wiring when new carpets were installed - but that's a long story.

I suggest you start by looking at the ARP cache listing on the router.
 You may be able to get the MAC address of the culprit.  That would at
least indicate the manufacturer of the offending NIC.  If that doesn't
work, I suggest that you work on the HUB side rather than travelling
from PC to PC.  Check the HUB ports for error conditions or the lights
on the HUB for weird activity. Check the connections & replace old
patch cords.  Next, you can then either troubleshoot macro style by
powering down one HUB at a time until you localize the problem or one
port at a time.  (Your users will really love you for this).   I've
been able to avoid many problems early on by using DHCP with an NT
server.  I also use WINS.  This not only eliminates the TCP/IP
administrative nightmare but it is kind of self documenting.  The IP
address/Mac Address/computer name listings can be found in the DHCP
administrator and the Machine NAME/Logon ID/IP address mapping can be
found in the WINS administrator.


-----Original Message-----
From:   Curt Brimacomb [mailto:[log in to unmask]]
Sent:   Tuesday, March 31, 1998 10:30 AM
To:     [log in to unmask]
Subject:        Duplicate IP address

Hello,

I have an error showing up on my Unix console (yes, I know this is the
3000
list).  it says:

Duplicate IP address: sent from Ethernet address 00:60:47:80:b3:ac.

Is the only way to track this down do go from PC to PC and check the
NIC for
this MAC address?

TIA

Curt Brimacomb
System Manager
                                       www.magiclink.com
Idaho Computer Services, Inc.                 [log in to unmask]
Voice:(208) 734-2245                                  Fax:(208)
733-9663