Docker Stack Deploy Does Not Work

Question

i am trying to deploy a stack to my docker swarm but it does not work. i call the command

sudo docker stack deploy -c docker-compose.yml server-test 

but it gives me the error

unsupported Compose file version: 2 

but when i run docker-compose up, it works fine. i then check the docker-compose --version which gives me:

docker-compose version 1.21.2, build a133471 

this is the latest version as of writing this. i'm fairly new to docker so any guidance on this is appreciated.

my docker-compose.yml file is as follows:

version: '2' services: caddy: build: . ports: - "80:80" - "443:443" portainer: image: portainer/portainer:latest ports: - "9000:9000" volumes: - "/var/run/docker.sock:/var/run/docker.sock" 

Answer 1

The error refers to version: '2' in the first line of docker-compose.yml. You need to change syntax to at least version: '3.0' then docker stack will work.

There is upgrade guide for docker-compose.yml.