How to fix Error response from daemon: network with name mynetwork already exists in Docker

First, verify the network exists and inspect its details:

docker network ls | grep mynetwork

To see full details of the existing network:

docker network inspect mynetwork

This shows which containers are connected to it and its configuration.

If the network already exists and has the configuration you need, simply use it. In docker-compose.yml, you can reference an existing external network:

networks:
  mynetwork:
    external: true

For docker run, just connect to the existing network:

docker run --network mynetwork myimage

If you want to recreate the network fresh, remove the existing one first:

docker network rm mynetwork

If containers are still connected to the network, you'll need to disconnect or stop them first:

# See what's connected
docker network inspect mynetwork --format '{{range .Containers}}{{.Name}} {{end}}'

# Disconnect a container
docker network disconnect mynetwork container_name

# Or stop all connected containers
docker stop $(docker network inspect mynetwork -f '{{range .Containers}}{{.Name}} {{end}}')

# Then remove the network
docker network rm mynetwork

The best approach for scripts and automation is to check before creating. Use this one-liner:

docker network inspect mynetwork >/dev/null 2>&1 || docker network create mynetwork

This inspects the network (silently) and only creates it if the inspect command fails.

For more robust scripts, use a filter with exact matching:

if [ -z "$(docker network ls --filter name=^mynetwork$ --format '{{.Name}}')" ]; then
  docker network create mynetwork
fi

The ^mynetwork$ regex ensures exact matching (not partial matches like "mynetwork2").

If you have multiple orphaned networks causing issues, clean them all up:

docker network prune

This removes all networks not used by at least one container. Add -f to skip the confirmation prompt:

docker network prune -f

Warning: This removes ALL unused networks, so make sure you don't need them.

Docker Compose creates networks named <project>_default or <project>_<network>. If you get conflicts:

Option 1: Bring down the old project properly:

docker-compose down

Option 2: Use a different project name:

docker-compose -p newproject up

Option 3: Force recreate everything:

docker-compose up --force-recreate