# docker_swarm – Manage Swarm cluster

New in version 2.7.

- Synopsis
- Requirements
- Parameters
- Notes
- Examples
- Return Values
- Status

## Synopsis

- Create a new Swarm cluster.
- Add/Remove nodes or managers to an existing cluster.

## Requirements

The below requirements are needed on the host that executes this module.

- Docker API >= 1.25
- Docker SDK for Python: Please note that the docker-py Python module has been superseded by docker (see here for details). For Python 2.6, `docker-py` must be used. Otherwise, it is recommended to install the `docker` Python module. Note that both modules should not be installed at the same time. Also note that when both modules are installed and one of them is uninstalled, the other might no longer function and a reinstall of it is required.
- Docker SDK for Python >= 1.10.0 (use docker-py for Python 2.6)

## Parameters

Parameter | Choices/Defaults | Comments
--- | --- | ---

advertise_addr
string

Externally reachable address advertised to other nodes.
This can either be an address/port combination in the form `192.168.1.1:4567`, or an interface followed by a port number, like `eth0:4567`.
If the port number is omitted, the port number from the listen address is used.
If advertise_addr is not specified, it will be automatically detected when possible.
Only used when swarm is initialised or joined. Because of this it's not considered for idempotency checking.

api_version
string

Default:
"auto"

The version of the Docker API running on the Docker Host.
Defaults to the latest version of the API supported by Docker SDK for Python and the docker daemon.
If the value is not specified in the task, the value of environment variable `DOCKER_API_VERSION` will be used instead. If the environment variable is not set, the default value will be used.
aliases: docker_api_version

autolock_managers
boolean

Choices:
- no
- yes

If set, generate a key and use it to lock data stored on the managers.
Docker default value is `no`.
docker_swarm_info can be used to retrieve the unlock key.

ca_cert path |  | Use a CA certificate when performing server verification by providing the path to a CA certificate file. If the value is not specified in the task and the environment variable `DOCKER_CERT_PATH` is set, the file `ca.pem` from the directory specified in the environment variable `DOCKER_CERT_PATH` will be used. aliases: tls_ca_cert, cacert_path
ca_force_rotate integer |  | An integer whose purpose is to force swarm to generate a new signing CA certificate and key, if none have been specified. Docker default value is `0`. Requires API version >= 1.30.
client_cert path |  | Path to the client's TLS certificate file. If the value is not specified in the task and the environment variable `DOCKER_CERT_PATH` is set, the file `cert.pem` from the directory specified in the environment variable `DOCKER_CERT_PATH` will be used. aliases: tls_client_cert, cert_path
client_key path |  | Path to the client's TLS key file. If the value is not specified in the task and the environment variable `DOCKER_CERT_PATH` is set, the file `key.pem` from the directory specified in the environment variable `DOCKER_CERT_PATH` will be used. aliases: tls_client_key, key_path

debug
boolean

Choices:
- no ←
- yes

Debug mode

default_addr_pool list / elements=string added in 2.8 |  | Default address pool in CIDR format. Only used when swarm is initialised. Because of this it's not considered for idempotency checking. Requires API version >= 1.39.
dispatcher_heartbeat_period integer |  | The delay for an agent to send a heartbeat to the dispatcher. Docker default value is `5s`.

docker_host
string

Default:
"unix://var/run/docker.sock"

The URL or Unix socket path used to connect to the Docker API. To connect to a remote host, provide the TCP connection string. For example, `tcp://192.0.2.23:2376`. If TLS is used to encrypt the connection, the module will automatically replace `tcp` in the connection URL with `https`.
If the value is not specified in the task, the value of environment variable `DOCKER_HOST` will be used instead. If the environment variable is not set, the default value will be used.
aliases: docker_url

election_tick integer |  | Amount of ticks (in seconds) needed without a leader to trigger a new election. Docker default value is `10s`.

force
boolean

Choices:
- no ←
- yes

Use with state `present` to force creating a new Swarm, even if already part of one.
Use with state `absent` to Leave the swarm even if this node is a manager.

heartbeat_tick integer |  | Amount of ticks (in seconds) between each heartbeat. Docker default value is `1s`.
join_token string |  | Swarm token used to join a swarm cluster. Used with state=join.
keep_old_snapshots integer |  | Number of snapshots to keep beyond the current snapshot. Docker default value is `0`.
labels dictionary |  | User-defined key/value metadata. Label operations in this module apply to the docker swarm cluster. Use docker_node module to add/modify/remove swarm node labels. Requires API version >= 1.32.

listen_addr
string

Default:
"0.0.0.0:2377"

Listen address used for inter-manager communication.
This can either be an address/port combination in the form `192.168.1.1:4567`, or an interface followed by a port number, like `eth0:4567`.
If the port number is omitted, the default swarm listening port is used.
Only used when swarm is initialised or joined. Because of this it's not considered for idempotency checking.

log_entries_for_slow_followers integer |  | Number of log entries to keep around to sync up slow followers after a snapshot is created.
name string |  | The name of the swarm.
node_cert_expiry integer |  | Automatic expiry for nodes certificates. Docker default value is `3months`.
node_id string |  | Swarm id of the node to remove. Used with state=remove.
remote_addrs list / elements=string |  | Remote address of one or more manager nodes of an existing Swarm to connect to. Used with state=join.

rotate_manager_token
boolean

Choices:
- no ←
- yes

Rotate the manager join token.

rotate_worker_token
boolean

Choices:
- no ←
- yes

Rotate the worker join token.

signing_ca_cert string |  | The desired signing CA certificate for all swarm node TLS leaf certificates, in PEM format. This must not be a path to a certificate, but the contents of the certificate. Requires API version >= 1.30.
signing_ca_key string |  | The desired signing CA key for all swarm node TLS leaf certificates, in PEM format. This must not be a path to a key, but the contents of the key. Requires API version >= 1.30.
snapshot_interval integer |  | Number of logs entries between snapshot. Docker default value is `10000`.
ssl_version string |  | Provide a valid SSL version number. Default value determined by ssl.py module. If the value is not specified in the task, the value of environment variable `DOCKER_SSL_VERSION` will be used instead.

state
string

Choices:
- present ←
- join
- absent
- remove
- inspect

Set to `present`, to create/update a new cluster.
Set to `join`, to join an existing cluster.
Set to `absent`, to leave an existing cluster.
Set to `remove`, to remove an absent node from the cluster. Note that removing requires Docker SDK for Python >= 2.4.0.
Set to `inspect` to display swarm informations.

subnet_size integer added in 2.8 |  | Default address pool subnet mask length. Only used when swarm is initialised. Because of this it's not considered for idempotency checking. Requires API version >= 1.39.
task_history_retention_limit integer |  | Maximum number of tasks history stored. Docker default value is `5`.
timeout integer | Default: 60 | The maximum amount of time in seconds to wait on a response from the API. If the value is not specified in the task, the value of environment variable `DOCKER_TIMEOUT` will be used instead. If the environment variable is not set, the default value will be used.

tls
boolean

Choices:
- no ←
- yes

Secure the connection to the API by using TLS without verifying the authenticity of the Docker host server. Note that if validate_certs is set to `yes` as well, it will take precedence.
If the value is not specified in the task, the value of environment variable `DOCKER_TLS` will be used instead. If the environment variable is not set, the default value will be used.

tls_hostname string | Default: "localhost" | When verifying the authenticity of the Docker Host server, provide the expected name of the server. If the value is not specified in the task, the value of environment variable `DOCKER_TLS_HOSTNAME` will be used instead. If the environment variable is not set, the default value will be used.

validate_certs
boolean

Choices:
- no ←
- yes

Secure the connection to the API by using TLS and verifying the authenticity of the Docker host server.
If the value is not specified in the task, the value of environment variable `DOCKER_TLS_VERIFY` will be used instead. If the environment variable is not set, the default value will be used.
aliases: tls_verify

## Notes

Note

- Connect to the Docker daemon by providing parameters with each task or by defining environment variables. You can define `DOCKER_HOST`, `DOCKER_TLS_HOSTNAME`, `DOCKER_API_VERSION`, `DOCKER_CERT_PATH`, `DOCKER_SSL_VERSION`, `DOCKER_TLS`, `DOCKER_TLS_VERIFY` and `DOCKER_TIMEOUT`. If you are using docker machine, run the script shipped with the product that sets up the environment. It will set these variables for you. See https://docs.docker.com/machine/reference/env/ for more details.
- When connecting to Docker daemon with TLS, you might need to install additional Python packages. For the Docker SDK for Python, version 2.4 or newer, this can be done by installing `docker[tls]` with pip.
- Note that the Docker SDK for Python only allows to specify the path to the Docker configuration for very few functions. In general, it will use `$HOME/.docker/config.json` if the `DOCKER_CONFIG` environment variable is not specified, and use `$DOCKER_CONFIG/config.json` otherwise.

## Examples

    - name: Init a new swarm with default parameters
      docker_swarm:
        state: present

    - name: Update swarm configuration
      docker_swarm:
        state: present
        election_tick: 5

    - name: Add nodes
      docker_swarm:
        state: join
        advertise_addr: 192.168.1.2
        join_token: SWMTKN-1--xxxxx
        remote_addrs: [ '192.168.1.1:2377' ]

    - name: Leave swarm for a node
      docker_swarm:
        state: absent

    - name: Remove a swarm manager
      docker_swarm:
        state: absent
        force: true

    - name: Remove node from swarm
      docker_swarm:
        state: remove
        node_id: mynode

    - name: Inspect swarm
      docker_swarm:
        state: inspect
      register: swarm_info

## Return Values

Common return values are documented here, the following are the fields unique to this module:

Key | Returned | Description
--- | --- | ---
actions list / elements=string | when action failed. | Provides the actions done on the swarm.
swarm_facts dictionary | success | Informations about swarm.
| JoinTokens dictionary | success | Tokens to connect to the Swarm.
|  | Manager string | success | Token to create a new *manager* node
|  | Worker string | success | Token to create a new *worker* node
| UnlockKey string | on success if autolock_managers is `true` and swarm is initialised, or if autolock_managers has changed. | The swarm unlock-key if autolock_managers is `true`.

## Status

- This module is not guaranteed to have a backwards compatible interface. [preview]
- This module is maintained by the Ansible Community. [community]

### Authors

- Thierry Bouvet (@tbouvet)
- Piotr Wojciechowski (@WojciechowskiPiotr)

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