Lack of VIP and Failover

Question

DB Version : 10.2.0.4
When VIP is functional , the CONNECTION REFUSED errors are quickly detected, and transparently the connection request will be transferred(fail over) to the next available IP.
If something goes wrong with your VIP , the failover will still happen but only after a substantial delay (until the TCP CONNECTION timeout is detected ). Am i Right?

Answer 1

Yes, this is TCP behaviour - nothing specifically to do with using virtual IP addresses.
The Oracle client driver will use the socket connect() call to initiate the TCP connection. It can take some time before this call fails with a ETIMEDOUT error. A ECONNREFUSED is usually immediate.
In case of a connect() failure, the client driver will then use the next IP address in the address list and try that (should the TNS provide an enumerated list of addresses).
The ETIMEDOUT error can result after a very long delay when the server owning that IP address has not yet completed loading (or shutting down) its IP stack or NIC. The ECONNREFUSED is usually immediate as the IP stack is up and running, and can respond directly with a "+no service listening on that port+" error.