high_availability
Description
The high_availability parameter determines whether to create a high availability (HA) cluster. When enabled, the router (nginx) and API components run with multiple replicas for redundancy. When disabled, they run with a single replica, reducing resource consumption.
Default Value
The default value for high_availability is true.
Use Cases
- Cost Optimization: Reduce infrastructure costs by running fewer replicas of system components.
- Development Environments: Use single-replica mode for non-production clusters where uptime is not critical.
- Production Resilience: Keep enabled in production for increased fault tolerance.
Setting Parameters
The high_availability parameter can only be set when the Rack is installed:
$ convox rack install azure <name> high_availability=false
It cannot be changed afterwards. convox rack params set rejects it with param 'high_availability' can only be set during rack installation.
Additional Information
When high_availability is true, the nginx ingress controller runs with 2-10 replicas (autoscaled) and the API runs with 2 replicas. When false, both run with a single replica.
