How to fix Error response from daemon: This node is not a swarm manager. Use 'docker swarm init' or 'docker swarm join' to connect this node to swarm in Docker

First, verify whether your Docker host is part of a swarm and what role it has:

docker info | grep -i swarm

If the output shows Swarm: inactive, the node is not in any swarm. If it shows Swarm: active with Is Manager: false, you're on a worker node.

You can also check with:

docker info --format '{{.Swarm.LocalNodeState}}'

This returns inactive, pending, active, or locked.

If you need overlay networks or other swarm features, initialize swarm mode:

docker swarm init

On a machine with multiple network interfaces, specify which IP to advertise:

docker swarm init --advertise-addr <your-ip-address>

After initialization, you can create overlay networks:

docker network create -d overlay --attachable my-overlay-network

The --attachable flag allows standalone containers (not just swarm services) to connect to the overlay network.

If you don't actually need multi-host networking, the simplest fix is to use the bridge driver instead of overlay. Bridge networks work without swarm mode.

In your docker-compose.yml, either remove the driver specification entirely (Docker Compose defaults to bridge):

networks:
  my_network:
    # No driver specified - defaults to bridge

Or explicitly specify bridge:

networks:
  my_network:
    driver: bridge

Then recreate the network:

docker-compose down
docker-compose up -d

If you're working with an existing swarm but running commands on the wrong node, you need to SSH into a manager node.

First, identify manager nodes from any node in the swarm:

docker node ls

This command only works from a manager node. If you're on a worker, check your infrastructure documentation or cloud console to find manager IPs.

You can also promote a worker to a manager from an existing manager:

docker node promote <node-name>

To demote back to worker:

docker node demote <node-name>

If the swarm state is corrupted or you need to start fresh, leave and reinitialize:

# Leave the current swarm (use --force if it's the last manager)
docker swarm leave --force

# Reinitialize
docker swarm init

Warning: Using --force on a manager will destroy the swarm if it's the only manager. All services, configs, and secrets will be lost.

If you need to rejoin an existing swarm, get a join token from a manager:

# On a manager node, get token for joining as worker
docker swarm join-token worker

# Or to join as a manager
docker swarm join-token manager

Then run the provided join command on the node you want to add.