aix errpt DUPLICATE IP ADDRESS DETECTED IN THE NET

errpt output shows: AIXIF_ARP_DUP_ADDR and error description is: DUPLICATE IP ADDRESS DETECTED IN THE NET
 

 Technote (troubleshooting)
 
Problem(Abstract)
Why am I logging an error in the errpt for a duplicate ipaddress. 
 
Symptom
LABEL:          AIXIF_ARP_DUP_ADDR
IDENTIFIER:     FE2DEE00

Date/Time:       Thu Jan 1 12:00:00 2008
Sequence Number: 1012
Machine Id:      XXXXXXXXXXXX
Node Id:         clkdns1
Class:           S
Type:            PERM
Resource Name:   SYSXAIXIF

Description
DUPLICATE IP ADDRESS DETECTED IN THE NET

Failure Causes
ARP RESPONSE RECEIVED FOR MY IP ADDRESS

       Recommended Actions
       CONTACT NETWORK ADMINISTRATOR

Detail Data
DUPLICATE IP ADDRESS
<hex number>
MAC ADDRESS
<hex number>
 
 
 
 
 
Resolving the problem
The reason you are logging this error in the errpt is due to the fact that AIX has received an ARP broadcast/unicast packet from another server.  That other server sent out a "gratuitous ARP" (gratuitous meaning it was not asked for by AIX).  This arp packet that AIX received indicated that another machine on the AIX subnet is using this ipaddress.
Normally you can take the <hex number> under the field: "MAC ADDRESS" in the errpt to your network admin, and find out which machine it is, and see if it is using the same ip as AIX.

There is currently a situation where AIX will receive an ARP packet from a Windows OS box that will look like an ARP telling AIX that the ip is already in use.  However, the Windows server is not using AIX's ipaddress.  This is a defect with the Broadcom adapter in the Windows server that causes this problem. This only happens when the Broadcom adapter is set up for Teaming in a Active/Active configuration. 

Please see below link:
http://www-947.ibm.com/systems/support/supportsite.wss/docdisplay?lndocid=MIGR-5075064&brandind=5000020

As a workaround to force the Windows server to stop sending AIX a gratuitous ARP packet, you must put the Windows in a Active/passive teaming configuration.  Another solution would be to unteam the adapters all together in the Windows server.  See broadcom for any device driver updates that may also provided a solution.  There is not any misconfiguration or problems on the AIX side. 

If AIX receives a gratuitous ARP from another Server that says that the other server is using AIX's ip, then the message will be logged in the errpt, there is no way to disable this on the AIX side.
 
 
 
from:https://www-304.ibm.com/support/docview.wss?uid=isg3T1010797&wv=1

 

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Tips:

There is/are some windows host(s) using network adapter bonding in the local domain of aix server!

Get all the MAC with same ip address,and find the windows host(s)!!