13.3.3 About the FAILOVER_MODE Parameters

The FAILOVER_MODE parameter supports these additional parameters. You can specify these in the CONNECT_DATA section of a connect descriptor.

Table 13-4 Additional Parameters of the FAILOVER_MODE Parameter

Parameter	Description
BACKUP	A different network service name for backup connections. A backup should be specified when using preconnect to pre-establish connections.
DELAY	The amount of time in seconds to wait between connect attempts. If RETRIES is specified, then DELAY defaults to one second. If a callback function is registered, then this parameter is ignored.
METHOD	The setting for fast failover from the primary node to the backup node: basic: Set to establish connections at failover time. This option requires almost no work on the backup server until failover time. preconnect: Set to pre-established connections. This provides faster failover but requires that the backup instance be able to support all connections from every supported instance.
RETRIES	The number of times to attempt to connect after a failover. If DELAY is specified, then RETRIES defaults to five retry attempts. If a callback function is registered, then this parameter is ignored.
TYPE	The type of failover. Three types of Oracle Net failover functionality are available by default to Oracle Call Interface (OCI) applications: session: Set to fail over the session. If the user's connection is lost, then a new session is automatically created for the user on the backup. This type of failover does not attempt to recover select operations. select: Set to enable users with open cursors to continue fetching on them after failure. However, this mode involves overhead on the client side in normal select operations. none: This is the default. No failover functionality is used. This can also be explicitly specified to prevent failover from happening.

Note:

Oracle Net Manager does not provide support for TAF parameters. These parameters must be set manually.