Solution

Issue:
How do I install GoldenGate on an Oracle RAC?

Solution Overview:
There are multiple variations of installing GoldenGate for Oracle RAC.

Solution Details:

Installing GoldenGate on Shared Drives

This approach works very well. The software is installed on shared drives that all the RAC nodes have access to. The manager and GoldenGate processes can be started from one of the nodes. If the node that the GoldenGate processes were started from fails, the checkpoints are maintained. The manager and GoldenGate processes then can be started from another node without making any modifications to any parameter files. If the database alone crashes on the node that GoldenGate was installed, then the manager process will need to be stopped on that node before it be restarted on another node.

Installing GoldenGate on local disk

This approach will not work in a fail over situation. If there was a database failure alone on this node, the software could be installed on a different node. For the replicat , all the trails would need to be moved to that node. The extract and replicat could be added and positioned to that last known good checkpoint. If there were a complete node failure, this would be very difficult to recover from. It would be impossible to know what the last good checkpoint was and we would have no access to any trails that were located on those local disks.

Connecting to the RAC instance from a application server using SQL*Net

The software is installed on a separate machine. GoldenGate is setup to connect to the RAC Instance via the Global Database name which is setup in TNSNAME.ORA. By connecting to the Global Database using SQL*Net, Oracle will handle the fail over. For extract, the oracle logs will need to be located on shared disk that this server has access to.

When adding your online Extract groups, be sure to specify the THREADS option on the ADD command.