Load Balancer Health checks
1 Background
Currently, the load balancing algorithms offered using CloudStack are only Round-Robin, Least Connections or source. There are no way to configure health checks that can be performed on the VMs.
Customer Benefits:
With Load Balancer performing health checks:
- Availability across zone failures: With the ability to perform health checks on the right set of parameters, the load balancer can service all of the requests in case of a VM failure or even a Zone failure. The load balancer would exactly know, based on the health check configured, that the service is unavailable as supposed to the VM being unavailable.
- Dynamic addition / removal of VMs: Once the health checks are configured, the load balancer can automatically remove a VM from load balancer pool if the health checks fail. Also, once the health checks are successful again, the load balancer can add the VMs back to the pool.
2 Requirements
- Users should be able to define health check policies as part of configuring the load balancer rules
- Feature needs to be supported on CS VR as well as all platforms of NS load balancers.
- Refer to AWS Health Check Configuration details for additional information and the screenshot below.
3 UI / UX Requirements
- UI should be changed to allow users to define health check policies.
4 Upgrade Scenarios
Following upgrade scenarios should be supported:
- No upgrade scenarios need to be handled, as this is a new functionality.
5 Non-Requirements
6 Bugs
7 Open Items: