RE: Oracle RAC and VIPs

From: Tao Wang <>
Date: Thu, 10 Jul 2008 13:59:55 -0400
Message-ID: <>

My understanding is that the listener on the surviving node, where the
VIP fails over to,  is not listening on the failed-over VIP, therefore
the listener can detect the failure right away. the client will use the
next entry in the tnsnames...




[] On Behalf Of Baumgartel, Paul
Sent: Thursday, July 10, 2008 1:04 PM
Subject: RE: Oracle RAC and VIPs


If the VIP comes up on another node, doesn't the attempt to connect to
that (virtual) IP translate to a connect to the other node?  If not, how
exactly is the failure detected right away?


Paul Baumgartel 
Information Technology 
Prime Services Databases Americas 
One Madison Avenue 
New York, NY 10010 
Phone 212.538.1143 




[] On Behalf Of Bradd Piontek
Sent: Thursday, July 10, 2008 10:16 AM
Subject: Re: Oracle RAC and VIPs

The basic gist is this:
  The VIP is a cluster resource managed by the clusterware. Depending on
your OS , you can see it running as a VIP under your public network NIC.
(ifconfig -a on Linux). What happens in a node failure is that the
clusterware brings that VIP resource up on another node so that when
clients attempt connects to that IP, the 'failure' is detected right
away and the client can use the next address in the tnsnames.ora entry
(or jdbc url, or whatever). 

Try it out sometime. take a node node, use srvctl to see where the vips
are running and look at the ifconfig to see as well.

On Thu, Jul 10, 2008 at 8:30 AM, Dba DBA <>

I have installed Rac. I know how to create a VIP. I don't understand why
this works. I also don't undertsand why TAF works. 

I am connected to node 1, how am I on the fly connected to node 2 if
node 1 goes down. 

Again, I know the functionality, I just don't know how it works under
the covers.

Can anyone help me out with this? 

Bradd Piontek

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Received on Thu Jul 10 2008 - 12:59:55 CDT

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