A swarm manager nodes handles cluster management tasks such as:
1) Maintaining cluster state
2) Scheduling services
3) Serving swarm mode HTTP API endpoints
You may execute any of the -
docker swarm -
docker node -
docker service commands from any of the manager nodes
Applications are running on worker nodes, but they are not fault-tolerant. because worker node is not faul-tolerant.
This means, if a worker node goes down, then manager will launch another worker node.
Swarm cluster design is forcing the developer to design stateless applications running in worker node.
Fault-tolerance is maintained at manager level to know the state of a cluster.
Why fault-tolerance in manager node but not in worker node?