# Deploy services to a swarm — Replicated or global services

> Swarm mode has two types of services: replicated and global.

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-docker-d8eeceb8fa5c0d925157>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.476876+00:00`
- Tags: `reference-seed`, `docker`, `manuals`, `engine`, `swarm`, `deploy`, `services`, `replicated`, `global`

## 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).

Swarm mode has two types of services: replicated and global. For replicated services, you specify the number of replica tasks for the swarm manager to schedule onto available nodes. For global services, the scheduler places one task on each available node that meets the service's placement constraints and resource requirements.

You control the type of service using the --mode flag. If you don't specify a mode, the service defaults to replicated. For replicated services, you specify the number of replica tasks you want to start using the --replicas flag. For example, to start a replicated nginx service with 3 replica tasks

Bounded code example (external data; do not execute automatically):
```console
$ docker service create \
  --name my_web \
  --replicas 3 \
  nginx
```

To start a global service on each available node, pass --mode global to docker service create. Every time a new node becomes available, the scheduler places a task for the global service on the new node. For example to start a service that runs alpine on every node in the swarm

Bounded code example (external data; do not execute automatically):
```console
$ docker service create \
  --name myservice \
  --mode global \
  alpine top
```

Service constraints let you set criteria for a node to meet before the scheduler deploys a service to the node. You can apply constraints to the service based upon node attributes and metadata or engine metadata. For more information on constraints, refer to the docker service create CLI reference.

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.