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 CREDIT SUISSE Information Technology Prime Services Databases Americas One Madison Avenue New York, NY 10010 USA Phone 212.538.1143 paul.baumgartel@xxxxxxxxxxxxxxxxx www.credit-suisse.com ________________________________ From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Bradd Piontek Sent: Thursday, July 10, 2008 10:16 AM To: oracledbaquestions@xxxxxxxxx Cc: oracle-l@xxxxxxxxxxxxx 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 <oracledbaquestions@xxxxxxxxx> wrote: 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 Twitter: http://www.twitter.com/piontekdd Oracle Blog: http://piontekdd.blogspot.com Linked In: http://www.linkedin.com/in/piontekdd Last.fm: http://www.last.fm/user/piontekdd/ ============================================================================== Please access the attached hyperlink for an important electronic communications disclaimer: http://www.credit-suisse.com/legal/en/disclaimer_email_ib.html ==============================================================================