Re: Regarding RAC vip failover and tnsnames entry

From: Rajeev Prabhakar <>
Date: Mon, 11 May 2009 14:45:44 -0400
Message-ID: <>


I would think, even if server side load balancing is used, second node's vip address
entry in the tnsnames would still be needed. How else would remote listener work
out in case of vip failure ? All listener know of "other" listeners via the tns entry of
the other nodes.

Also, here is what Oracle manual says :

   (address=(protocol=tcp)(host=node1-vip)(port=1521))    (address=(protocol=tcp)(host=node2-vip)(port=1521)))

That said, I have myself never tried the vip failure related testing without the 2nd
node entry. If I misunderstood you, please let me know.


On Mon, May 11, 2009 at 2:03 PM, Bradd Piontek <> wrote:
> Not to sound contradictory (although I am contradicting what Riyaj wrote),
> but the 2nd node is note 'required' to be in the tnsnames.ora if Server-Side
> Load balancing is in place and you are using the VIP address. All listeners
> on all nodes know of the other listeners, and can re-route traffic to a
> different node. What is required is that the DNS entry spit back to the
> client from the listener needs to be able to be resolved by the client.
> As with just about anything, especially with RAC, it is important that you
> test out all these types of scenarios and see how your application reacts to
> these types of events. (regardless of what the manual says 'should'
> happen). Just $0.02.
> Bradd Piontek

Received on Mon May 11 2009 - 13:45:44 CDT

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