Enabling failover in a multiple node Oracle RAC database cluster

You can enable failover in a multiple node Oracle RAC database cluster in UNIX/Linux by using traditional RAC or RAC with SCAN.

To enable failover in a multiple node Oracle RAC database cluster, perform the following steps:

  1. Open the /<install_dir>/properties directory to modify the sandbox.cfg file.
  2. In the sandbox.cfg file, add a ORACLE_JDBC_URL property, which contains the Oracle RAC connection URL.

    Choose one of the following option depending on whether you are using traditional RAC or RAC with SCAN. The property value must be one string of text that starts with ORACLE_JDBC_URL=. Your database administrator (DBA) can modify this URL as needed:

    • To configure traditional RAC, use this format:
      jdbc:oracle:thin:@
      (DESCRIPTION=
       (ADDRESS_LIST= 
        (FAILOVER=ON)
        (LOAD_BALANCE=OFF)
        (ADDRESS=(PROTOCOL=TCP)(HOST=myhost1)(PORT=1521))
        (ADDRESS=(PROTOCOL=TCP)(HOST=myhost2)(PORT=1521))
       )
        (CONNECT_DATA = (SERVER = DEDICATED)(SERVICE_NAME=myservicename OR mySID))
       )
      Note: This method uses the default Oracle RAC service that is provided by Oracle.
    • To configure RAC with SCAN, use this format:
      jdbc:oracle:thin:@host:port/service

      For example:

      jdbc:oracle:thin:@RAC-SCAN:1521/ORCL

      Where:

      • RAC-SCAN is resolved to an IP address by DNS
      • 1521 = Port number
      • ORCL = the name of your Oracle RAC service
        Important: To use RAC with SCAN, you must also define a new Oracle RAC service (you cannot use the default service) that defines one node as the preferred node and at least one node as a failover node.
  3. Open the /<install_dir>/bin directory.
  4. Enter the command ./setupfiles.sh.