The customer is still not convinced about the advantages of using node VIPs. Which is the most
important point that will convince him about why VIPs are used in Oracle RAC 12cR1 environments?
A.
It is very convenient as whenever a node/interface/network related to the node VIP falls, the VIP
can fail to another node and the failed over VIP can start accepting connections from the new node
avoiding connection failures.
B.
This is needed as whenever a node/interface/network related to the node VIP fails, clients that
attempt to connect to the VIP address receive a rapid connection-refused error Instead of waiting
for TCP connect timeout messages. This helps for a quicker failure detection and resolution.
C.
It is needed as whenever the node/interface/network related to the VIP fails, nothing happens
and node VIP never fails to any other node and stays stable.
D.
Configuring VIP is optional and not needed in an Oracle RAC 12cR1 configuration.
http://logicalread.solarwinds.com/virtual-ip-with-oracle-rac-mc04/#.WIfhi1N97IU
The response given to the client will generally be in the form of an ORA-12541, advising that no listener is available. This is because the node where the VIP now resides has its own listener, but it is listening on its own VIP, not the VIP of any other nodes. The client, receiving the message that there is no listener, will then immediately retry, using the next IP in the ADDRESS_LIST, rather than waiting up to 2 minutes for the timeout we would normally expect. Thus, a connect-time failover has still occurred, but the connection attempt succeeds within a second or even faster. Even though a client uses the SCAN, the local listener is still listening on the VIP.