98 lines
2.7 KiB
YAML
98 lines
2.7 KiB
YAML
command: docker service scale
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short: Scale one or multiple replicated services
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long: |-
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The scale command enables you to scale one or more replicated services either up
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or down to the desired number of replicas. This command cannot be applied on
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services which are global mode. The command will return immediately, but the
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actual scaling of the service may take some time. To stop all replicas of a
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service while keeping the service active in the swarm you can set the scale to 0.
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> **Note**
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>
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> This is a cluster management command, and must be executed on a swarm
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> manager node. To learn about managers and workers, refer to the
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> [Swarm mode section](https://docs.docker.com/engine/swarm/) in the
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> documentation.
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usage: docker service scale SERVICE=REPLICAS [SERVICE=REPLICAS...]
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pname: docker service
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plink: docker_service.yaml
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options:
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- option: detach
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shorthand: d
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value_type: bool
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default_value: "false"
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description: |
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Exit immediately instead of waiting for the service to converge
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deprecated: false
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min_api_version: "1.29"
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experimental: false
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experimentalcli: false
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kubernetes: false
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swarm: false
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examples: |-
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### Scale a single service
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The following command scales the "frontend" service to 50 tasks.
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```bash
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$ docker service scale frontend=50
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frontend scaled to 50
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```
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The following command tries to scale a global service to 10 tasks and returns an error.
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```bash
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$ docker service create --mode global --name backend backend:latest
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b4g08uwuairexjub6ome6usqh
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$ docker service scale backend=10
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backend: scale can only be used with replicated mode
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```
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Directly afterwards, run `docker service ls`, to see the actual number of
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replicas.
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```bash
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$ docker service ls --filter name=frontend
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ID NAME MODE REPLICAS IMAGE
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3pr5mlvu3fh9 frontend replicated 15/50 nginx:alpine
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```
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You can also scale a service using the [`docker service update`](service_update.md)
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command. The following commands are equivalent:
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```bash
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$ docker service scale frontend=50
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$ docker service update --replicas=50 frontend
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```
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### Scale multiple services
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The `docker service scale` command allows you to set the desired number of
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tasks for multiple services at once. The following example scales both the
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backend and frontend services:
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```bash
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$ docker service scale backend=3 frontend=5
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backend scaled to 3
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frontend scaled to 5
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$ docker service ls
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ID NAME MODE REPLICAS IMAGE
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3pr5mlvu3fh9 frontend replicated 5/5 nginx:alpine
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74nzcxxjv6fq backend replicated 3/3 redis:3.0.6
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```
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deprecated: false
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min_api_version: "1.24"
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experimental: false
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experimentalcli: false
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kubernetes: false
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swarm: true
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