Documentation Grafana Agent Flow mode Reference Components reference discovery.nomad

discovery.nomad

discovery.nomad allows you to retrieve scrape targets from Nomad’s Service API.

Usage

river Copy

discovery.nomad "LABEL" {
}

Arguments

The following arguments are supported:

At most, one of the following can be provided:

• bearer_token argument.
• bearer_token_file argument.
• basic_auth block.
• authorization block.
• oauth2 block.

no_proxy can contain IPs, CIDR notations, and domain names. IP and domain names can contain port numbers. proxy_url must be configured if no_proxy is configured.

proxy_from_environment uses the environment variables HTTP_PROXY, HTTPS_PROXY and NO_PROXY (or the lowercase versions thereof). Requests use the proxy from the environment variable matching their scheme, unless excluded by NO_PROXY. proxy_url and no_proxy must not be configured if proxy_from_environment is configured.

proxy_connect_header should only be configured if proxy_url or proxy_from_environment are configured.

Blocks

The following blocks are supported inside the definition of discovery.nomad:

The > symbol indicates deeper levels of nesting. For example, oauth2 > tls_config refers to a tls_config block defined inside an oauth2 block.

basic_auth block

password and password_file are mutually exclusive, and only one can be provided inside a basic_auth block.

authorization block

credential and credentials_file are mutually exclusive, and only one can be provided inside an authorization block.

oauth2 block

client_secret and client_secret_file are mutually exclusive, and only one can be provided inside an oauth2 block.

The oauth2 block may also contain a separate tls_config sub-block.

no_proxy can contain IPs, CIDR notations, and domain names. IP and domain names can contain port numbers. proxy_url must be configured if no_proxy is configured.

proxy_from_environment uses the environment variables HTTP_PROXY, HTTPS_PROXY and NO_PROXY (or the lowercase versions thereof). Requests use the proxy from the environment variable matching their scheme, unless excluded by NO_PROXY. proxy_url and no_proxy must not be configured if proxy_from_environment is configured.

proxy_connect_header should only be configured if proxy_url or proxy_from_environment are configured.

tls_config block

The following pairs of arguments are mutually exclusive and can’t both be set simultaneously:

• ca_pem and ca_file
• cert_pem and cert_file
• key_pem and key_file

When configuring client authentication, both the client certificate (using cert_pem or cert_file) and the client key (using key_pem or key_file) must be provided.

When min_version is not provided, the minimum acceptable TLS version is inherited from Go’s default minimum version, TLS 1.2. If min_version is provided, it must be set to one of the following strings:

• "TLS10" (TLS 1.0)
• "TLS11" (TLS 1.1)
• "TLS12" (TLS 1.2)
• "TLS13" (TLS 1.3)

Exported fields

The following fields are exported and can be referenced by other components:

Each target includes the following labels:

• __meta_nomad_address: the service address of the target.
• __meta_nomad_dc: the datacenter name for the target.
• __meta_nomad_namespace: the namespace of the target.
• __meta_nomad_node_id: the node name defined for the target.
• __meta_nomad_service: the name of the service the target belongs to.
• __meta_nomad_service_address: the service address of the target.
• __meta_nomad_service_id: the service ID of the target.
• __meta_nomad_service_port: the service port of the target.
• __meta_nomad_tags: the list of tags of the target joined by the tag separator.

Component health

discovery.nomad is only reported as unhealthy when given an invalid configuration. In those cases, exported fields retain their last healthy values.

Debug information

discovery.nomad does not expose any component-specific debug information.

Debug metrics

discovery.nomad does not expose any component-specific debug metrics.

Example

This example discovers targets from a Nomad server:

river Copy

discovery.nomad "example" {
}

prometheus.scrape "demo" {
  targets    = discovery.nomad.example.targets
  forward_to = [prometheus.remote_write.demo.receiver]
}

prometheus.remote_write "demo" {
  endpoint {
    url = PROMETHEUS_REMOTE_WRITE_URL

    basic_auth {
      username = USERNAME
      password = PASSWORD
    }
  }
}

Replace the following:

• PROMETHEUS_REMOTE_WRITE_URL: The URL of the Prometheus remote_write-compatible server to send metrics to.
• USERNAME: The username to use for authentication to the remote_write API.
• PASSWORD: The password to use for authentication to the remote_write API.

Compatible components

discovery.nomad has exports that can be consumed by the following components:

• Components that consume Targets