Set up high availability

MKE is designed to facilitate high availability (HA). You can join multiple manager nodes to the cluster, so that if one manager node fails, another one can automatically take its place without impacting the cluster.

Including multiple manager nodes in your cluster allows you to handle manager node failures and load-balance user requests across all manager nodes.

The following table exhibits the relationship between the number of manager nodes used and the number of faults that your cluster can tolerate:

Manager nodes

Failures tolerated

1

0

3

1

5

2

For deployment into product environments, follow these best practices:

  • For HA with minimal network overhead, Mirantis recommends using three manager nodes and a maximum of five. Adding more manager nodes than this can lead to performance degradation, as configuration changes must be replicated across all manager nodes.

  • You should bring failed manager nodes back online as soon as possible, as each failed manager node decreases the number of failures that your cluster can tolerate.

  • You should distribute your manager nodes across different availability zones. This way your cluster can continue working even if an entire availability zone goes down.