Configuring Failover and Load Balancing

Client load balancing is when a client will randomly choose between the listeners for its connect requests. When client load balancing is set to ON, Net8 balances the load over the list of listener addresses by picking one at random. When set to OFF, Net8 uses the elements in the list in the order in which they are provided.

Failover is when a client connect fails over to a different listener if the first listener fails. When failover is set to on, Net8 proceeds through all the listener addresses until one succeeds.

Note: The Net8 Assistant only supports load balancing and failover for an ADDRESS_LIST. If you require load balancing and failover for a DECRIPTION_ LIST, you must configure the TNSNAMES.ORA file manually. See the Net8 Administrator’s Guide.

To configure fail over and load balancing:

  1. Double-click on the Net Service Names folder in the directory tree.

  2. Click on an existing net service name that has multiple addresses configured.

  3. Click Advanced in the Address Configuration group window.

  4. Ensure the Use Options Compatible with Net8 8.0 Clients option is turned off.

  5. Select one of the following options:

    Try each address, in order, until one succeeds:

    Select this option to turn on the fail over feature for release 8.1 client. If the first address cannot be reached, fail over, allows the client to use the next listener address.

    Try each address, randomly, until one succeeds:

    Select this option to turn on load balancing and fail over features for a release 8.1 client.

    Try one address, selected at random:

    Select this option to turn on the load balancing feature for a release 8.1 client. Load balancing randomly chooses between listener addresses.

  6. Click OK.

  7. Choose Save Network Configuration from the File menu to save changes to TNSNAMES.ORA in $ORACLE_HOME/network/admin on UNIX or ORACLE_HOME\network\admin on Windows platforms, or choose Save As from the File menu to save under a different file name or path.