Load-Balancing with data guard

Hi Hamdi, the database query in question in used to determine the state of the database, OPEN or not. So, if both your Active and Standby database servers are in a big-ip pool, during normal operation, the Active will be "up", and the Standby will be "down". When there is a transition from Active to Standby ( via Dataguard Manager or other process ), then health monitor will show the reverse...the Active will be "down", and the Standby will now be "up" ( becoming the new Active ). Then big-ip will begin to send connections to the Standby, as soon as the monitor ( database query ) returns the OPEN status to the big-ip.

 

 

This monitor does not control the actual transistion, it detects the change in state, and routes connections to the current OPEN database.

 

 

Hope this helps clarify the use case for this.

 

 

-Chris.