The “failover” column displays special information for servers operating in high availability environments. In high availability environments, prepared transactions may be transferred to a secondary companion server if the original server experiences a critical failure. The “failover” column can display three possible failover states that indicate how and where the transaction is executing:
“Resident Tx” is displayed under normal operating conditions, and on systems that do not utilize Adaptive Server high availability features. “Resident Tx” means that the transaction was started and is executing on a primary Adaptive Server.
Failed-over Tx” is displayed after there has been a failover to a secondary companion server. “Failed-over Tx” means that a transaction originally started on a primary server and reached the prepared state, but was automatically migrated to the secondary companion server (for example, as a result of a system failure on the primary server). The migration of a prepared transaction occurs transparently to an external coordinating service.
Tx by Failover-Conn” is also displayed after there has been a failover to a secondary companion server. “Tx by Failover-Conn” indicates that the application or client attempted to start the transaction on a primary server, but the primary server was not available due to a connection failover. When this occurs, the transaction is automatically started on the secondary companion server, and the transaction is marked “Tx by Failover-Conn”.
See “Transaction failover information” for more information about Adaptive Server failover features.
