A service is a group of containers with the same image:tag.

It makes it easy to scale your application (i.e. you just increase the number of containers in the service).

To create a new service use

docker service create

Note – this must be run on a Swarm manager.

e.g.

docker service create -d --name pinger --replicas 2 --network ubernet alpine sleep 1d

List with:

docker service ls

Check which nodes they’re on with:

docker service ps pinger

and, switching to that node, we can check the network with:

docker network inspect ubernet

which shows the service under Containers.

Switching to the second replica we should see the task by doing a:

docker container ls