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Warning: this command is part of the Swarm management feature introduced in Docker 1.12, and might be subject to non backward-compatible changes.
service scale
Usage: docker service scale SERVICE=REPLICAS [SERVICE=REPLICAS...]
Scale one or multiple services
Options:
--help Print usage
Examples
Scale a service
If you scale a service, you set the desired number of replicas. Even though the command returns directly, actual scaling of the service may take some time.
For example, the following command scales the "frontend" service to 50 tasks.
$ docker service scale frontend=50
frontend scaled to 50
Directly afterwards, run docker service ls, to see the actual number of
replicas
$ docker service ls --filter name=frontend
ID NAME REPLICAS IMAGE COMMAND
3pr5mlvu3fh9 frontend 15/50 nginx:alpine
You can also scale a service using the docker service update
command. The following commands are therefore equivalent:
$ docker service scale frontend=50
$ docker service update --replicas=50 frontend
Scale multiple services
The docker service scale command allows you to set the desired number of
tasks for multiple services at once. The following example scales both the
backend and frontend services:
$ docker service scale backend=3 frontend=5
backend scaled to 3
frontend scaled to 5
$ docker service ls
ID NAME REPLICAS IMAGE COMMAND
3pr5mlvu3fh9 frontend 5/5 nginx:alpine
74nzcxxjv6fq backend 3/3 redis:3.0.6