rtld: 0712-001 Symbol CreateIoCompletionPort was referenced

In My Case Cause of below the issue at storage level.
failing currently due to LVM inconsistency

For more Detail follow below the reference links.

Ref: 
http://oracle-help.com/ora-errors/rtld-0712-001-symbol-createiocompletionport-was-referenced/
AIX 12.1.0.2 Installation Fails with "rtld: 0712-001 Symbol CreateIoCompletionPort was referenced " (Doc ID 1949184.1)

Highly Available VIP (HAVIP)

Highly Available IP (HAIP) comes from 11.2.0.2 on-words and maximum 4 define for Private network.

Now in 12c version introduces Highly Available VIP (HAVIP) a Clusterware-monitored VIP that can be used for non-Databaseapplications.

Typically, VIPs are created for VIP or SCAN listeners for Database connections. In some cases, the need arises to create a VIP monitored by Clusterware designed to support other applications.

For more Detail : Click Here

New feature in Oracle 11g database to kill session

Now we can kill session after finishing existing transaction to be finished. Means in previous release there was no scope to finish on going transaction. Instead of "alter system kill session" here we can use "alter system disconnect session". Using syntax "POST_TRANSACTION" we can kill session for active transaction has to be completed first and after that it will be automatically killed. Example of same syntax is given below.

SQL> alter system disconnect session '10,251' post_transaction;
System altered.

LREG New BG Process In 12c

In 11.2 Pmon process propogates the service metrics to the listeners regitered in local_listener adn remote_listener initialization parameter.

As the remote_listener specifies specifies the address of scan listener and the local_listener parameter specifies the address of the VIP listener, PMON process propogates the service metrics to both SCAN and VIP listeners.

You can trace listener registration using the following command.

alter system set event='immediate trace name listener_registration level 15';

Now in 12c version listener registration is permed by a new mandatory background process named LREG.

And if you want to trace then LREG trace file getting to all info about listener registration.

Advantage : Not recommneding that you create 50+ of unnecessary services,you should create

as many services as you need to split the application into manageable and disjointed workload.

In 11gR2 if there are 50+/100+ services and listeners then there is a possiblilyt that the PMON process

might spend more time on service registration to listener.

But in 12c this possibility is eliminated as the LREG backgroud process which is totally dedicated for registering the services to Listener.

and PMON is freed from listener registration.

PRCD-1027 PRCD-1229

PRCD-1027 : Failed to retrieve database racdb
PRCD-1229 : An attempt to access configuration of database racdb was rejected because its version 11.2.0.1.0 differs from the program version 11.2.0.4.0. Instead run the program from /oracle/product/11.2.0/db_1.



[root@rac1 ~]# srvctl status database -d racdb
PRCD-1027 : Failed to retrieve database racdb
PRCD-1229 : An attempt to access configuration of database racdb was rejected because its version 11.2.0.1.0 differs from the program version 11.2.0.4.0. Instead run the program from /oracle/product/11.2.0/db_1.

[root@rac1 ~]# srvctl config database -d racdb

PRCD-1027 : Failed to retrieve database racdb
PRCD-1229 : An attempt to access configuration of database racdb was rejected because its version 11.2.0.1.0 differs from the program version 11.2.0.4.0. Instead run the program from /oracle/product/11.2.0/db_1.

[root@rac1 ~]# srvctl config database
racdb


-- First Attempt
[root@rac1 ~]# srvctl modify database -d racdb -o /oracle/product/11204/db_1

PRCD-1027 : Failed to retrieve database racdb
PRCD-1229 : An attempt to access configuration of database racdb was rejected because its version 11.2.0.1.0 differs from the program version 11.2.0.4.0. Instead run the program from /oracle/product/11.2.0/db_1.

-- Second Attempt
[root@rac1 ~]# srvctl upgrade database -d  racdb -o /oracle/product/11204/db_1

PRCD-1231 : Failed to upgrade configuration of database racdb to version 11.2.0.4.0 in new Oracle home /oracle/product/11204/db_1
PRKH-1014 : Current user "root" is not the oracle owner user "oracle" of oracle home "/oracle/product/11204/db_1"

[root@rac1 ~]# su - oracle

-- Final Attempt
[oracle@rac1 ~]$ srvctl upgrade database -d  racdb -o /oracle/product/11204/db_1

[oracle@rac1 ~]$ exit
logout

[root@rac1 ~]# srvctl status database -d racdb
Instance racdb1 is running on node rac1
Instance racdb2 is running on node rac2