Redeploy in swarm (1 replica) is not killing previous instance

[yur0n]

To Reproduce

1. Create app
2. Choose registry and 1 replica so the app is added to swarm
3. Deploy
4. Redeploy using webhook

Current vs. Expected behavior

Following the steps from the previous section, I expect the service would shutdown and redeploy, but observe that another instance of the app is created each redeploy alongside previously deployed instance and Traefik is balancing between these instances

Provide environment information

Operating System: OS: Ubuntu 22
Dokploy version: 0.21.5
Deploying Node.js app

Which area(s) are affected? (Select all that apply)

Docker, Traefik, Application

Are you deploying the applications where Dokploy is installed or on a remote server?

Same server where Dokploy is installed

Additional context

Changing the replica number to 5, redeploying, changing the replica number to 1, redeploying - fixes the issue until next redeploy

Will you send a PR to fix it?

No

[Siumauricio]

I dont see any issues here

screen-recording-2025-07-05-at-53854-pm_kejeek9c.mp4

This is the expected behaviour because we use docker swarm underneath for the applications

What happens is that when a new deploy or redeploy is done, the old container is deleted and a new one is created, unlike if we did it with a standalone container if it would be that case it would be turned off and on again but here is different we use docker swarm so this behaviour is different.

[yur0n]

What happens is that when a new deploy or redeploy is done, the old container is deleted and a new one is created

That is what I'm talking about, the old container(-s) is not being deleted and still working alongside new container with Traefik balancing between these containers

[gertjanjansen]

@yur0n and @Siumauricio I might be able to help reproduce because I just encountered the exact same issue @yur0n described. For every new deployment, Dokploy was adding a new container without deleting the previous one. Every new deploy was adding an additional container.

Example:

root@newserver:~# docker service ls
ID             NAME                       MODE         REPLICAS   IMAGE                          PORTS
t5n6fca3jln7   test-app-api-lknog1        replicated   3/1        test-app-api-lknog1:latest

As you can see, I had 3 replicas where it should've been 1.

It turns out this happened because I didn't select a registry:

As soon as I selected a registry here, stopped all containers and redeployed, it all worked as expected.

Maybe selecting a registry should be required?

(My setup: 2 fresh servers, one running Dokploy, the other connected as a swarm node)