github.com/iqoqo/nomad@v0.11.3-0.20200911112621-d7021c74d101/website/pages/docs/integrations/consul-integration.mdx (about)

     1  ---
     2  layout: docs
     3  page_title: Consul Integration
     4  sidebar_title: Consul
     5  description: Learn how to integrate Nomad with Consul and add service discovery to jobs
     6  ---
     7  
     8  # Consul Integration
     9  
    10  [Consul][] is a tool for discovering and configuring services in your
    11  infrastructure. Consul's key features include service discovery, health checking,
    12  a KV store, and robust support for multi-datacenter deployments. Nomad's integration
    13  with Consul enables automatic clustering, built-in service registration, and
    14  dynamic rendering of configuration files and environment variables. The sections
    15  below describe the integration in more detail.
    16  
    17  ## Configuration
    18  
    19  In order to use Consul with Nomad, you will need to configure and
    20  install Consul on your nodes alongside Nomad, or schedule it as a system job.
    21  Nomad does not currently run Consul for you.
    22  
    23  To enable Consul integration, please see the
    24  [Nomad agent Consul integration](/docs/configuration/consul)
    25  configuration.
    26  
    27  ## Automatic Clustering with Consul
    28  
    29  Nomad servers and clients will be automatically informed of each other's
    30  existence when a running Consul cluster already exists and the Consul agent is
    31  installed and configured on each host. Please see the [Automatic Clustering with
    32  Consul](https://learn.hashicorp.com/nomad/operating-nomad/clustering) guide for more information.
    33  
    34  ## Service Discovery
    35  
    36  Nomad schedules workloads of various types across a cluster of generic hosts.
    37  Because of this, placement is not known in advance and you will need to use
    38  service discovery to connect tasks to other services deployed across your
    39  cluster. Nomad integrates with Consul to provide service discovery and
    40  monitoring.
    41  
    42  To configure a job to register with service discovery, please see the
    43  [`service` job specification documentation][service].
    44  
    45  ## Dynamic Configuration
    46  
    47  Nomad's job specification includes a [`template` stanza](/docs/job-specification/template)
    48  that utilizes a Consul ecosystem tool called [Consul Template](https://github.com/hashicorp/consul-template). This mechanism creates a convenient way to ship configuration files
    49  that are populated from environment variables, Consul data, Vault secrets, or just
    50  general configurations within a Nomad task.
    51  
    52  For more information on Nomad's template stanza and how it leverages Consul Template,
    53  please see the [`template` job specification documentation](/docs/job-specification/template).
    54  
    55  ## Assumptions
    56  
    57  - Consul 0.7.2 or later is needed for `tls_skip_verify` in HTTP checks.
    58  
    59  - Consul 0.6.4 or later is needed for using the Script checks.
    60  
    61  - Consul 0.6.0 or later is needed for using the TCP checks.
    62  
    63  - The service discovery feature in Nomad depends on operators making sure that
    64    the Nomad client can reach the Consul agent.
    65  
    66  - Tasks running inside Nomad also need to reach out to the Consul agent if
    67    they want to use any of the Consul APIs. Ex: A task running inside a docker
    68    container in the bridge mode won't be able to talk to a Consul Agent running
    69    on the loopback interface of the host since the container in the bridge mode
    70    has its own network interface and doesn't see interfaces on the global
    71    network namespace of the host. There are a couple of ways to solve this, one
    72    way is to run the container in the host networking mode, or make the Consul
    73    agent listen on an interface in the network namespace of the container.
    74  
    75  [consul]: https://www.consul.io/ 'Consul by HashiCorp'
    76  [service]: /docs/job-specification/service 'Nomad service Job Specification'