github.com/kobeld/docker@v1.12.0-rc1/docs/swarm/index.md (about)

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     3  title = "Swarm overview"
     4  description = "Docker Swarm overview"
     5  keywords = ["docker, container, cluster, swarm"]
     6  [menu.main]
     7  identifier="swarm_overview"
     8  parent="engine_swarm"
     9  weight="1"
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    12  <![end-metadata]-->
    13  # Docker Swarm overview
    14  
    15  To use this version of Swarm, install the Docker Engine `v1.12.0-rc1` or later
    16  from the [Docker releases GitHub
    17  repository](https://github.com/docker/docker/releases). Alternatively, install
    18  the latest Docker for Mac or Docker for Windows Beta.
    19  
    20  Docker Engine 1.12 includes Docker Swarm for natively managing a cluster of
    21  Docker Engines called a Swarm. Use the Docker CLI to create a Swarm, deploy
    22  application services to the Swarm, and manage the Swarm behavior.
    23  
    24  
    25  If you’re using a Docker version prior to `v1.12.0-rc1`, see [Docker
    26  Swarm](https://docs.docker.com/swarm).
    27  
    28  ## Feature highlights
    29  
    30  * **Cluster management integrated with Docker Engine:** Use the Docker Engine
    31  CLI to create a Swarm of Docker Engines where you can deploy application
    32  services. You don't need additional orchestration software to create or manage
    33  a Swarm.
    34  
    35  * **Decentralized design:** Instead of handling differentiation between node
    36  roles at deployment time, Swarm handles any specialization at runtime. You can
    37  deploy both kinds of nodes, managers and workers, using the Docker Engine.
    38  This means you can build an entire Swarm from a single disk image.
    39  
    40  * **Declarative service model:** Swarm uses a declarative syntax to let you
    41  define the desired state of the various services in your application stack.
    42  For example, you might describe an application comprised of a web front end
    43  service with message queueing services and a database backend.
    44  
    45  * **Desired state reconciliation:** Swarm constantly monitors the cluster state
    46  and reconciles any differences between the actual state your expressed desired
    47  state.
    48  
    49  * **Multi-host networking:** You can specify an overlay network for your
    50  application. Swarm automatically assigns addresses to the containers on the
    51  overlay network when it initializes or updates the application.
    52  
    53  * **Service discovery:** Swarm assigns each service a unique DNS name and load
    54  balances running containers. Each Swarm has an internal DNS server that can
    55  query every container in the cluster using DNS.
    56  
    57  * **Load balancing:** Using Swarm, you can expose the ports for services to an
    58  external load balancer. Internally, Swarm lets you specify how to distribute
    59  service containers between nodes.
    60  
    61  * **Secure by default:** Each node in the Swarm enforces TLS mutual
    62  authentication and encryption to secure communications between itself and all
    63  other nodes. You have the option to use self-signed root certificates or
    64  certificates from a custom root CA.
    65  
    66  * **Scaling:** For each service, you can declare the number of instances you
    67  want to run. When you scale up or down, Swarm automatically adapts by adding
    68  or removing instances of the service to maintain the desired state.
    69  
    70  * **Rolling updates:** At rollout time you can apply service updates to nodes
    71  incrementally. Swarm lets you control the delay between service deployment to
    72  different sets of nodes. If anything goes wrong, you can roll-back an instance
    73  of a service.
    74  
    75  ## What's next?
    76  * Learn Swarm [key concepts](key-concepts.md).
    77  * Get started with the [Swarm tutorial](swarm-tutorial/index.md).
    78  
    79  <p style="margin-bottom:300px">&nbsp;</p>