FailoverEvent Enumeration

FailoverEvent enumerated values are used to specify the state of the failover.

Table 12-7 lists all the FailoverEvent enumeration values with a description of each enumerated value.

Table 12-7 FailoverEvent Enumeration Values

Member Names Description


Indicates that failover has detected a lost connection and that failover is starting.


Indicates successful completion of failover.


Indicates that failover was unsuccessful, and there is no option of retrying.


Indicates that failover was unsuccessful, and it gives the application the opportunity to handle the error and retry failover. The application can retry failover by returning FailoverReturnCode.Retry for the event notification.


Indicates that a user handle has been reauthenticated. This applies to the situation where a client has multiple user sessions on a single server connection. During the initial failover, only the active user session is failed over. Other sessions are failed over when the application tries to use them. This is the value passed to the callback during these subsequent failovers.

No significant database operation should occur immediately after a FailoverEvent.Begin event. SQL and major database operations should wait until the FailoverEvent.End event. FailoverEvent.Begin is primarily used to reject failover or to trace it. FailoverEvent.Begin can also be used for non-database application operations, such as informing the end user a failover is in progress and to wait until it completes before proceeding. Transactions can be used in the FailoverEvent.End callback phase, such as to file fault tickets or audit. These transactions must be committed before the callback completes.


Provider ODP.NET, Unmanaged Driver





.NET Framework