Hello, there! I have a WAN federated Consul DC with some separate DC. It works fine, but now I want to add my k8s Consul instance into this federated DC. Official helm chart support only mesh-federation. Is it possible to change federation type to mesh without downtime?
To upgrade your traditional WAN federation to Mesh-enabled, downtime is unavoidable. This is because when you enable the mesh (meshGateway.enabled: true), a new set of mesh gateway pods with new routable addresses, though not Consul servers, will be created as the frontend within Kubernetes, and these will communicate with another federated DC.
Alternative, you may consider to join your new Consul k8s to the existing Consul cluster. This docs may help you.