# Deploy services to a swarm — Update a service

> You can change almost everything about an existing service using the docker service update command.

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-docker-22f467a47fd4621826a4>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.464615+00:00`
- Tags: `reference-seed`, `docker`, `manuals`, `engine`, `swarm`, `deploy`, `services`, `update`, `service`

## Provenance

- Source: <https://github.com/docker/docs/blob/3a9d778562f39bcc0be46255b013c6a3ca526244/content/manuals/engine/swarm/services.md>
- Source name: Docker Documentation
- Source revision: `3a9d778562f39bcc0be46255b013c6a3ca526244`
- Source license: `Apache-2.0`
- Attribution and license details: <https://wikikv.com/licenses>

## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

You can change almost everything about an existing service using the docker service update command. When you update a service, Docker stops its containers and restarts them with the new configuration.

Since Nginx is a web service, it works much better if you publish port 80 to clients outside the swarm. You can specify this when you create the service, using the -p or --publish flag. When updating an existing service, the flag is --publish-add. There is also a --publish-rm flag to remove a port that was previously published.

Assuming that the my_web service from the previous section still exists, use the following command to update it to publish port 80.

Bounded code example (external data; do not execute automatically):
```console
$ docker service update --publish-add 80 my_web
```

To verify that it worked, use docker service ls

Bounded code example (external data; do not execute automatically):
```console
$ docker service ls

ID                  NAME                MODE                REPLICAS            IMAGE                                                                                             PORTS
4nhxl7oxw5vz        my_web              replicated          1/1                 docker.io/library/nginx@sha256:41ad9967ea448d7c2b203c699b429abe1ed5af331cd92533900c6d77490e0268   *:0-&gt;80/tcp
```

For more information on how publishing ports works, see publish ports.

You can update almost every configuration detail about an existing service, including the image name and tag it runs. See Update a service's image after creation.

Attribution: Adapted from Docker Documentation under Apache-2.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.