Can't communicate correctly across 2 nodes through overlay network

Hi everyone,

I’m discovering Docker Swarm and I’m struggling to deploy services in an overlay network (and make it work).
I’m using docker stack deploy -c config.yml studio with this simple compose file

version: "3.4"
    image: redis
    image: postgres
    attachable: true
    driver: overlay
    internal: false

The services are well deployed across my 2 nodes (1 service on each node), but the weird thing starts now.
I run watch -n 1 docker network inspect studio_default on the manager to have real-time status of my network, and I noticed that in the Peers field, the worker node appears and disappears randomly, so the service deployed on the node is “randomly available/reachable”.
Why the node disconnects itself from the network (and reconnects) ?

I can ping from the manager container to the worker one when the node appears in the Peers, but I think I can’t even ping from the worker to the manager…

I’m lost :frowning: