Rancher Deployment Strategy
There are two recommended deployment strategies for a Rancher server that manages downstream Kubernetes clusters. Each one has its own pros and cons. Read more about which one would fit best for your use case:
Hub & Spoke Strategy
In this deployment scenario, there is a single Rancher control plane managing Kubernetes clusters across the globe. The control plane would be run on a high-availability Kubernetes cluster, and there would be impact due to latencies.
Pros
- Environments could have nodes and network connectivity across regions.
- Single control plane interface to view/see all regions and environments.
- Kubernetes does not require Rancher to operate and can tolerate losing connectivity to the Rancher control plane.
Cons
- Subject to network latencies.
- If the control plane goes out, global provisioning of new services is unavailable until it is restored. However, each Kubernetes cluster can continue to be managed individually.
Regional Strategy
In the regional deployment model a control plane is deployed in close proximity to the compute nodes.
Pros
- Rancher functionality in regions stay operational if a control plane in another region goes down.
- Network latency is greatly reduced, improving the performance of functionality in Rancher.
- Upgrades of the Rancher control plane can be done independently per region.
Cons
- Overhead of managing multiple Rancher installations.
- Visibility across global Kubernetes clusters requires multiple interfaces/panes of glass.
- Deploying multi-cluster apps in Rancher requires repeating the process for each Rancher server.