we are running two node active/active Oracle11g R2 RAC cluster i need to replace public network cables on each node. I am planning to do as given below:


  • OS: oracle Solaris 11.1 Sparc
  • Database : oracle11g R2 RAC dual node cluster using ASM
  • Middle tier : Microsoft Dot net apps servers
  • Client tier : Internet explorer ( BUI )

Public NW Cable replacement Action Plan:

  1. Prepared and ensured the 2 new Public network cables one for each node
  2. Check and verify the Database status using srvctl
  3. first from node 1 i will remove the cable from both (switch port & server port) simultaneously and replace it with the new cable with in few seconds.
  4. Check and verify the instance status on the new cable (node1) and wait for 5 minutes
  5. Repeat the steps 2-3 for the node2.
  6. Check and verify the instance status and wait for some time to ensure the both the instacnes are up and running
  7. Test the application

Note: Initially check and ensure the Apps servers tnsnames.ora configuration ( SCAN Names / VIP/node's local ip ) Using SCAN-Names recommended if not observe carefully the TAF behaviour on the node side and the application side as well )

Kindly review the above steps and guide me.

MShafi - Senior System admin Abu Dhabi - UAE

  • Do you only want to change the cables or do you also change the IP segment of your server?
    – jmk
    Jan 29, 2015 at 8:25
  • Don't you have IPMP (aka bonding) on your public and heartbeat interfaces?
    – jmk
    Jan 29, 2015 at 8:35

2 Answers 2


Just from Oracle side there is nothing to worry about. You could even do this operation during normal business hours.

BUT! most Applications are not cluster ready. They cannot deal with this situation and will crash. All services are still available since they are migrated to the second node. But the session does not get migrated that's why the client will loose the connection. An application which supports RAC would then reopen the connection and just continue to work.

I would plan a downtime for this operation.

For the future you could bond two network ports for the public interface in failover mode. With that setup you could do the operation without downtime. Note that bonding in load balance mode does not work so well -- at least this is my experience.


you should be aware that RAC works on private IP (aka heartbeat IP). unlesss you disturb that you can modify the network settings. also that VLAN will be in different from your local LAN.

since you are using RAC you can even stop the db on node1 and perform the action and then start the service which will not take much time. repeat the same for node 2.

hope this helps

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