Scenario: What happens to client traffic after a BlackBerry MDS Integration Service instance stops responding
When a BlackBerry® MDS Integration Service instance in a BlackBerry MDS Integration Service pool stops responding, the BlackBerry MDS Integration Service clients or hardware load balancer redirect traffic differently depending on whether you configure DNS round robin or a hardware load balancer.
How BlackBerry MDS Integration Service clients redirect traffic when you configure DNS round robin
- The BlackBerry MDS Integration Service client loses its connection to a BlackBerry MDS Integration Service instance.
- The BlackBerry MDS Integration Service client excludes the IP address of the nonresponsive BlackBerry MDS Integration Service instances from the list of IP addresses of the BlackBerry MDS Integration Service pool temporarily.
- The BlackBerry MDS Integration Service client tries to connect to the next IP address in the list of BlackBerry MDS Integration Service instances in the BlackBerry MDS Integration Service pool.
- If the BlackBerry MDS Integration Service client is a BlackBerry MDS Connection Service instance, the BlackBerry MDS Connection Service instance determines that the BlackBerry MDS Integration Service instance is not healthy and sends the health score to the BlackBerry Dispatcher. You can check the health status of the BlackBerry MDS Integration Service pool by viewing the health parameters in the BlackBerry Administration Service.
How the hardware load balancer redirects client traffic when you configure a hardware load balancer
- The hardware load balancer detects that a BlackBerry MDS Integration Service instance stopped responding.
- The hardware load balancer removes the BlackBerry MDS Integration Service instance from the pool automatically.
- The hardware load balancer redirects the BlackBerry MDS Integration Service client requests to another BlackBerry MDS Integration Service instance in the pool automatically.
When you configure a hardware load balancer, the health parameter for the nonresponsive BlackBerry MDS Integration Service instance does not change to indicate the health status of the BlackBerry MDS Integration Service pool. You can detect that a BlackBerry MDS Integration Service instance is not responding when you try to manage the BlackBerry MDS Integration Service instance using the BlackBerry Administration Service and the BlackBerry Administration Service cannot make the changes.