Duplicate IP address detected

[ej7257]

Nimble CS240

Firmware v2.2.5.0

Ever since we upgraded firmware to 2.2.5.0 (which was a real pain by the way) we started receiving "duplicate IP address detected" warnings on our CS240:

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-Subject: Nimble Alert on NIMBLEDR / NIMBLEDR (AA-######) - WARNING: Duplicate IP Address Detected

-

-Time: Fri May  1 08:23:11 2015

-

-Type: 12212

-Id: 27337

-Message: A duplicate of IP address 10.50.50.111 is found in the network.

-

-Group Name: NIMBLEDR

-Group ID: 9098228026317961766

-Array name: NIMBLEDR

-Serial: AA-######

-Version: 2.2.5.0-197583-opt

-

-Arrays in the group:

----------------------+-----------------+-----------+----------------+-----------

-Name Serial            Model       Version          Status

----------------------+-----------------+-----------+----------------+-----------

-NIMBLEDR AA-######         CS240       2.2.5.0-197583-opt reachable 

--------------------------------------------------------------------------------------------------------------------------------------------------------------------

The alerts happen once a day but never at the same time of day.

We have not made any changes to the network configuration, no additional hardware was connected to the iSCSI switch (HP ProCurve 1800 with no CLI or logs unfortunately).

The duplicate IPs listed in the alerts are the four ethernet interfaces on the Nimble which have not changed since initial setup two years ago.

Does anyone have any suggestions? We are at a loss at this point. There does not seem to be any service interruption and support has not been able to find the root cause.

Thank you.

[rfenton4]

Hi Erik,

You could run:

c:\arp -a 10.50.50.111

This should return a list of the MAC addresses associated with that IP address. To see if these match up to the MAC address's on the array (available on the Manage > Arrays screen)

I'd advise putting a call into support so they can take a look at the logs and assist isolating this issue

Cheers

Rich

[ej7257]

Unfortunately we had an open case with support and they were not able to find any cause in the logs. Quite the coincidence though that it only started happening after a firmware upgrade...

Thank you for the suggestion, but the arp cache has no entries for these IP addresses.

[ej7257 · Accepted solution]

The iSCSI switch is connected to our Cisco core switch. We turned off Proxy ARP on the Cisco core switch and that fixed the duplicate IP alerts from the Nimble.

[rfenton4]

Thanks for updating the thread Erik - glad that's sorted