Failover Connections for Data Guard Error with ORA-1033 [ID 461874.1]-CFANZ编程社区

Failover Connections for Data Guard Error with ORA-1033 [ID 461874.1]

	Modified 28-SEP-2010 Type PROBLEM Status PUBLISHED

In this Document
Symptoms Cause Solution

Applies to:

Oracle Net Services - Version: 9.2.0.1.0 to 10.2.0.1.0 - Release: 9.2 to 10.2
Information in this document applies to any platform.

Symptoms

Connections in data guard environment fail with ORA-01033: ORACLE initialization or shutdown in progress.

Oracle Net client trace shows after successful connection handshake

Net service name has LOAD_BALANCE set in description section

(DESCRIPTION = (LOAD_BALANCE = yes) (ADDRESS = (PROTOCOL = TCP)(HOST = NodeA)(PORT = 1521)) (ADDRESS = (PROTOCOL = TCP)(HOST = NodeB)(PORT = 1521))

Or has two description sections

(DESCRIPTION_LIST = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(Host = NodeA)(Port = 1521)) (CONNECT_DATA = (SERVICE_NAME = ORCL1) ) ) (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(Host = NodeB)(Port = 1521)) (CONNECT_DATA = (SERVICE_NAME = ORCL2)

Cause

Error ORA-1033 is expected for connections when they attempt to connect to standby instance, because it is mounted and not open.

When LOAD_BALANCE is set, connections can load balance between the addresses in the net service name.

When there are two description sections in a net service name, Oracle Net will load balance between them.

Solution

Example is for service called failover

1. Setup the net service name, ensuring LOAD_BALANCE is not used and one has one description section.

DGtest = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = NodeA)(PORT = 1521)) (ADDRESS = (PROTOCOL = TCP)(HOST = NodeB)(PORT = 1521)) ) (CONNECT_DATA = (SERVICE_NAME = failover) (SERVER = DEDICATED) (FAILOVER_MODE = (TYPE = session) (METHOD = BASIC) (RETRIES = 180) (DELAY = 5) ) ) ) )

2. Create and start service

SQL> exec DBMS_SERVICE.CREATE_SERVICE (service_name => 'failover',network_name => 'failover',aq_ha_notifications => true,failover_method => 'BASIC', failover_type => 'SELECT',failover_retries => 180,failover_delay => 1);
PL/SQL procedure successfully completed.

SQL>exec dbms_service.start_service('failover');
PL/SQL procedure successfully completed.

3.Create a database trigger to ensure the service name is always the same, no matter which node's instance is the primary.

sqlplus / as sysdba
SQL> CREATE OR REPLACE TRIGGER manage_OCIservice after startup on database DECLARE role VARCHAR(30); BEGIN SELECT DATABASE_ROLE INTO role FROM V$DATABASE; IF role = 'PRIMARY' THEN DBMS_SERVICE.START_SERVICE('failover'); ELSE DBMS_SERVICE.STOP_SERVICE('failover'); END IF; END;
PL/SQL procedure successfully completed.

4. Ensure the change is made on the standby with command.

SQL> Alter system archive log current ;

5. Listener service command lsnrctl services on primary will then show

Service "failover" has 1 instance(s). Instance "tom1", status READY, has 1 handler(s) for this service... Handler(s): "DEDICATED" established:0 refused:0 state:ready LOCAL SERVER

This method ensures the service failover is only available on the primary node.The net service name DGtest works through the addresses in the address_list section, in order. If NodeA is the standby, then Node B will have the service failover and the connection will attempt to connect.

More information on Dataguard setup can be found in following articles:
Note 316740.1How to configure to let TAF work after Data Guard Switchover or Failover

http://www.oracle.com/technology/deploy/availability/htdocs/maa.htm http://www.oracle.com/technology/deploy/availability/pdf/MAA_WP_10gR2_ClientFailoverBestPractices.pdf