open-nomad/website/source/docs/service-discovery/index.html.md

layout	page_title	sidebar_current	description
docs	Service Discovery	docs-service-discovery	Learn how to add service discovery to jobs

Service Discovery

Nomad schedules workloads of various types across a cluster of generic hosts. Because of this, placement is not known in advance and you will need to use service discovery to connect tasks to other services deployed across your cluster. Nomad integrates with Consul to provide service discovery and monitoring.

Note that in order to use Consul with Nomad, you will need to configure and install Consul on your nodes alongside Nomad, or schedule it as a system job. Nomad does not currently run Consul for you.

Configuration

To enable Consul integration, please see the Nomad agent Consul integration configuration.

Service Definition Syntax

To configure a job to register with service discovery, please see the service job specification documentation.

Assumptions

• Consul 0.7.2 or later is needed for tls_skip_verify in HTTP checks.

• Consul 0.6.4 or later is needed for using the Script checks.

• Consul 0.6.0 or later is needed for using the TCP checks.

• The service discovery feature in Nomad depends on operators making sure that the Nomad client can reach the Consul agent.

• Tasks running inside Nomad also need to reach out to the Consul agent if they want to use any of the Consul APIs. Ex: A task running inside a docker container in the bridge mode won't be able to talk to a Consul Agent running on the loopback interface of the host since the container in the bridge mode has its own network interface and doesn't see interfaces on the global network namespace of the host. There are a couple of ways to solve this, one way is to run the container in the host networking mode, or make the Consul agent listen on an interface in the network namespace of the container.