Error Message

AIX's errpt output at the time of the IP address onlining:
 

LABEL:          AIXIF_ARP_DUP_ADDR
IDENTIFIER:     XXXXXX

Date/Time:       Mon XXXXXX
Sequence Number: XXXXX
Machine Id:      XXXXXX
Node Id:         XXXXXXXX
Class:           S
Type:            PERM
WPAR:            Global
Resource Name:   XXXXXXXXX

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
XXXXX XXXX
MAC ADDRESS
XXXX XXXX XXXX
 

During analysis, the errpt output was found to report a duplicate IP address during boot time of the system, i.e. it was evident that an IP address (under VCS control) had actually been onlined before VCS and outside of its control. Upon further investigation, it was apparent that the OS command - chdev - had been run to cause the AIX operating system to online the additional virtual IP address concerned at boot time. This was determined by use of "lsattr -El , e.g. lsattr -El en0

This finding could also be corroborated by consulting the AIX Object Data Manager (ODM) in Veritas Explorer. The IP addressed concerned could be seen in the /objrepos/CuAt.odm file. Files listed is this directory are dumps of ODM device configuration information, e.g., how devices will be configured on boot. 

It is not supported to use the OS's chdev command to make a virtual IP address persistently online at boot time when the same IP address is configured to online within VCS. Should this be done, it will likely result in duplicate IP address warnings across a cluster.

Remove any virtual IP alias configured in AIX ODM for devices to let VCS handle online/offline of virtual IP addresses.

 

Virtual IP address brought online by AIX operating system before VCS causing duplicate IP address error.

Error Message

AIX's errpt output at the time of the IP address onlining:
LABEL: AIXIF_ARP_DUP_ADDR
IDENTIFIER: XXXXXX Date/Time: Mon XXXXXX
Sequence Number: XXXXX
Machine Id: XXXXXX
Node Id: XXXXXXXX
Class: S
Type: PERM
WPAR: Global
Resource Name: XXXXXXXXX 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
XXXXX XXXX
MAC ADDRESS
XXXX XXXX XXXX

Cause

During analysis, the errpt output was found to report a duplicate IP address during boot time of the system, i.e. it was evident that an IP address (under VCS control) had actually been onlined before VCS and outside of its control. Upon further investigation, it was apparent that the OS command - chdev - had been run to cause the AIX operating system to online the additional virtual IP address concerned at boot time. This was determined by use of "lsattr -El <Device_Name>, e.g. lsattr -El en0 This finding could also be corroborated by consulting the AIX Object Data Manager (ODM) in Veritas Explorer. The IP addressed concerned could be seen in the /objrepos/CuAt.odm file. Files listed is this directory are dumps of ODM device configuration information, e.g., how devices will be configured on boot.

Solution

It is not supported to use the OS's chdev command to make a virtual IP address persistently online at boot time when the same IP address is configured to online within VCS. Should this be done, it will likely result in duplicate IP address warnings across a cluster. Remove any virtual IP alias configured in AIX ODM for devices to let VCS handle online/offline of virtual IP addresses.