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service create

Usage:  docker service create [OPTIONS] IMAGE [COMMAND] [ARG...]

Create a new service

Options:
      --constraint value             Placement constraints (default [])
      --endpoint-mode string         Endpoint mode (vip or dnsrr)
  -e, --env value                    Set environment variables (default [])
      --help                         Print usage
  -l, --label value                  Service labels (default [])
      --limit-cpu value              Limit CPUs (default 0.000)
      --limit-memory value           Limit Memory (default 0 B)
      --log-driver string            Logging driver for service
      --log-opt value                Logging driver options (default [])
      --mode string                  Service mode (replicated or global) (default "replicated")
      --mount value                  Attach a mount to the service
      --name string                  Service name
      --network value                Network attachments (default [])
  -p, --publish value                Publish a port as a node port (default [])
      --registry-auth                Send registry authentication details to Swarm agents
      --replicas value               Number of tasks (default none)
      --reserve-cpu value            Reserve CPUs (default 0.000)
      --reserve-memory value         Reserve Memory (default 0 B)
      --restart-condition string     Restart when condition is met (none, on-failure, or any)
      --restart-delay value          Delay between restart attempts (default none)
      --restart-max-attempts value   Maximum number of restarts before giving up (default none)
      --restart-window value         Window used to evaluate the restart policy (default none)
      --stop-grace-period value      Time to wait before force killing a container (default none)
      --update-delay duration        Delay between updates
      --update-parallelism uint      Maximum number of tasks updated simultaneously
  -u, --user string                  Username or UID
  -w, --workdir string               Working directory inside the container

Creates a service as described by the specified parameters. This command has to be run targeting a manager node.

Examples

Create a service

$ docker service create --name redis redis:3.0.6
dmu1ept4cxcfe8k8lhtux3ro3

$ docker service ls
ID            NAME   REPLICAS  IMAGE        COMMAND
dmu1ept4cxcf  redis  1/1       redis:3.0.6

Create a service with 5 tasks

You can set the number of tasks for a service using the --replicas option. The following command creates a redis service with 5 tasks:

$ docker service create --name redis --replicas=5 redis:3.0.6
4cdgfyky7ozwh3htjfw0d12qv

The above command sets the desired number of tasks for the service. Even though the command returns directly, actual scaling of the service may take some time. The REPLICAS column shows both the actual and desired number of tasks for the service.

In the following example, the desired number of tasks is set to 5, but the actual number is 3

$ docker service ls
ID            NAME    REPLICAS  IMAGE        COMMAND
4cdgfyky7ozw  redis   3/5       redis:3.0.7

Once all the tasks are created, the actual number of tasks is equal to the desired number:

$ docker service ls
ID            NAME    REPLICAS  IMAGE        COMMAND
4cdgfyky7ozw  redis   5/5       redis:3.0.7

Create a service with a rolling update policy

$ docker service create \
  --replicas 10 \
  --name redis \
  --update-delay 10s \
  --update-parallelism 2 \
  redis:3.0.6

When this service is updated, a rolling update will update tasks in batches of 2, with 10s between batches.

Setting environment variables (-e --env)

This sets environmental variables for all tasks in a service. For example:

$ docker service create --name redis_2 --replicas 5 --env MYVAR=foo redis:3.0.6

Set metadata on a service (-l --label)

A label is a key=value pair that applies metadata to a service. To label a service with two labels:

$ docker service create \
  --name redis_2 \
  --label com.example.foo="bar"
  --label bar=baz \
  redis:3.0.6

For more information about labels, refer to apply custom metadata.

Set service mode

Is this a replicated service or a global service. A replicated service runs as many tasks as specified, while a global service runs on each active node in the swarm.

The following command creates a "global" service:

$ docker service create --name redis_2 --mode global redis:3.0.6

Specify service constraints

You can limit the set of nodes where a task can be scheduled by defining constraint expressions. Multiple constraints find nodes that satisfy every expression (AND match). Constraints can match node or Docker Engine labels as follows:

node attribute	matches	example
node.id	node ID	`node.id == 2ivku8v2gvtg4`
node.hostname	node hostname	`node.hostname != node-2`
node.role	node role: manager	`node.role == manager`
node.labels	user defined node labels	`node.labels.security == high`
engine.labels	Docker Engine's labels	`engine.labels.operatingsystem == ubuntu 14.04`

engine.labels apply to Docker Engine labels like operating system, drivers, etc. Swarm administrators add node.labels for operational purposes by using the docker node update command.

For example, the following limits tasks for the redis service to nodes where the node type label equals queue:

$ docker service create \
  --name redis_2 \
  --constraint 'node.labels.type == queue' \
  redis:3.0.6

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