In below representation <Domain 1> as denoted as Green and <Domain 2> as Blue.

Description of the illustration 1.4_oracle-traffic-director.png

The Blue-Green deployment process uses two identical environments-Blue and Green. Only one environment is active at a time, serving all the traffic with the load balancer and the other environment is in the standby mode.

Example, let us consider that Blue is in standby and Green is active. When the updates are completed in the Blue environment, you can use the load balancer to switch the traffic to the Blue environment.

Once the Traffic is diverted and directed to the Blue environment using the Load balancer. Health checks are performed for all the components of the currently active Blue environment with traffic.