This section provides information about how to troubleshoot certain issues that customers may encounter when using Replication Manager with Oracle.
For automatic discovery of the Oracle databases several Oracle queries are run at the start of the replication. Whenever Replication Manager operations fail with Oracle SQL errors it is important to get the result of some of the queries.
Connection failure
When the Replication Manager agent can’t connect to the Oracle database at configuration or replication time, check the following aspects of your environment:
1. Determine if the TNS listener or Oracle Name Service is up and running.
2. Run tnsping <service identifier> to make sure that Oracle connection works.
3. Make sure the Oracle service is up and running. Run the SQLPLUS command:
select * from dba_data_files
88 EMC Replication Manager Integration with Oracle Database Server Unable to create the backup control file
If Replication Manager is unable to create the backup control file, follow these steps to troubleshoot the issue:
1. Make sure that the /tmp directory is not full.
2. Set the environment variables ORACLE_SID and ORACLE_HOME.
3. Run the command $ORACLE_HOME/bin/sqlplus <user/password @ Oracle Service> as sysdba.
4. Alter the database backup control file to $ERM_TEMP_BASE/filename.
(where ERM_TEMP_BASE could be /tmp or any other location specified in rc.irclient) 5. In RAC configurations only, this error can occur when the application set was defined against the
database rather than a specific SID corresponding to one of the RAC nodes.
Some important Oracle errors and possible causes
Table 4 shows some important Oracle errors and provides possible causes and solutions to these error situations.
Table 4 Oracle errors, causes, and solutions
Error Cause/Solution
ORA-12154:
TNS could not resolve the service name
Identify where the TNS configuration files can be found on the host.
Check that the TNSNAMES.ora file is in the default location or if not, update the TNS_ADMIN field accordingly on the
"Create Application Set" screen.
Check the SQLNET.ora file and identify the order for the service resolution is as follows: TNS, ONAMES
Check the TNSNAMES.ora file and see if the service is correctly defined.
Run tnsping for the service and check the output for the hostname and port number.
ORA-12560:
TNS protocol adapter error
Check whether tnsping for the service identifier works correctly.
89 EMC Replication Manager Integration with Oracle Database Server
Error Cause/Solution
ORA-12505:
"TNS:listener does not currently know of SID given in connect descriptor"
This means that the listener that handled the connection request doesn't know of the SID described in the descriptor defined in the tns alias in tnsnames.ora. This can happen especially in "offline" situations such as offline replications or restore, where Replication Manager has to connect back to an instance that is in idle state.
Make sure that the listener being started is the expected one. By default, Oracle uses a listener called "LISTENER". So commands such as lsnrctl start/stop with no argument will act on the default listener. If the listener defined in listener.ora is not referred to by the default name (for
example, LISTENER_RAC), then its explicit name needs to be mentioned in the listener commands (lsnrctl start LISTENER_RAC, lsnrctl status LISTENER_RAC). The way to verify that the listener is listening to the SID requests is by running the status
command: lsnrctl status <listener name>
or lsnrctl services <listener name>.
90 EMC Replication Manager Integration with Oracle Database Server
Conclusion
This white paper explains how to use Replication Manager with Oracle Database Server, including how to configure your Oracle environment for optimal replica
creation. The paper also describes the details associated with creating an application set and a job to replicate Oracle data with Replication Manager. These sections describe the details of how to create a replica, including important information about setting credentials, discovering the Oracle environment, planning your replica layout, and so on. In addition, the white paper reviews consistency settings and optional files that Replication Manager can replicate.
Other parts of the paper describe such advanced Oracle subjects as replicating the Flash Recovery Area, replicating data stored under an Automatic Storage Management instance, and restoring Oracle data in varied Oracle configurations.
The white paper describes various mount techniques in detail, including specifics of how Replication Manager carries out mounts such as a mount to the production host.
The mount section also describes how various mount options affect the resulting mount and there is also a section devoted to the impact of mount on future restores of the mounted replica. Finally, a troubleshooting section provides solutions to some issues that Oracle users might encounter when replicating their data with Replication Manager.
References
For more information on Replication Manager and how to use it in your Oracle environment, consider the following sources:
EMC Replication Manager Product Guide
EMC Replication Manager Administrator's Guide EMC Replication Manager Release Notes
For more information on replication technologies in conjunction with Oracle Block Change Tracking, consider the following source:
Reducing Backup Window and Recovery Time with Oracle Database 11g RMAN and EMC TimeFinder/Clone