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content/manuals/engine/swarm/swarm-tutorial/scale-service.md
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---
description: Scale the service running in the swarm
keywords: tutorial, cluster management, swarm mode, scale, get started
title: Scale the service in the swarm
weight: 50
notoc: true
---

Once you have [deployed a service](deploy-service.md) to a swarm, you are ready
to use the Docker CLI to scale the number of containers in
the service. Containers running in a service are called tasks.

1.  If you haven't already, open a terminal and ssh into the machine where you
    run your manager node. For example, the tutorial uses a machine named
    `manager1`.

2.  Run the following command to change the desired state of the
    service running in the swarm:

    ```console
    $ docker service scale <SERVICE-ID>=<NUMBER-OF-TASKS>
    ```

    For example:

    ```console
    $ docker service scale helloworld=5

    helloworld scaled to 5
    ```

3.  Run `docker service ps <SERVICE-ID>` to see the updated task list:

    ```console
    $ docker service ps helloworld

    NAME                                    IMAGE   NODE      DESIRED STATE  CURRENT STATE
    helloworld.1.8p1vev3fq5zm0mi8g0as41w35  alpine  worker2   Running        Running 7 minutes
    helloworld.2.c7a7tcdq5s0uk3qr88mf8xco6  alpine  worker1   Running        Running 24 seconds
    helloworld.3.6crl09vdcalvtfehfh69ogfb1  alpine  worker1   Running        Running 24 seconds
    helloworld.4.auky6trawmdlcne8ad8phb0f1  alpine  manager1  Running        Running 24 seconds
    helloworld.5.ba19kca06l18zujfwxyc5lkyn  alpine  worker2   Running        Running 24 seconds
    ```

    You can see that swarm has created 4 new tasks to scale to a total of 5
    running instances of Alpine Linux. The tasks are distributed between the
    three nodes of the swarm. One is running on `manager1`.

4.  Run `docker ps` to see the containers running on the node where you're
    connected. The following example shows the tasks running on `manager1`:

    ```console
    $ docker ps

    CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
    528d68040f95        alpine:latest       "ping docker.com"   About a minute ago   Up About a minute                       helloworld.4.auky6trawmdlcne8ad8phb0f1
    ```

    If you want to see the containers running on other nodes, ssh into
    those nodes and run the `docker ps` command.

## Next steps

At this point in the tutorial, you're finished with the `helloworld` service. Next, you'll delete the service

{{< button text="Delete the service" url="delete-service.md" >}}

Chunks
805b75c5 (1st chunk of `content/manuals/engine/swarm/swarm-tutorial/scale-service.md`)
Title: Scaling a Service in a Docker Swarm
Summary
This section of the tutorial explains how to scale a service within a Docker Swarm using the Docker CLI. It involves connecting to the manager node, using `docker service scale` to adjust the number of tasks, and verifying the changes using `docker service ps` and `docker ps` to see the distribution of containers across the swarm nodes. The next step is to delete the service.