[robbyt]

Docker is a amazing tool, but I think the technical design and overall strategy for Swarm wasn't very well executed. Moving to k8s is a smart thing for them, because it's objectively better for real production use.

In our tests about a year ago, swarm started showing serious networking and cluster synchronization problems with cluster sizes over 30 nodes (physical servers), on a fast, reliable LAN.

I've heard similar stories from another big Docker customer- Docker support promised them that improving performance of Swarm and fixing scaling issues are the focus of "the next version", but they never came. This company is now moving to k8s.