Open source


discovery.dns discovers scrape targets from DNS records.


discovery.dns "LABEL" {
  names = [NAME_1, NAME_2, ...]


The following arguments are supported:

nameslist(string)DNS names to look up.yes
portnumberPort to use for collecting metrics. Not used for SRV records.0no
refresh_intervaldurationHow often to query DNS for updates."30s"no
typestringType of DNS record to query. Must be one of SRV, A, AAAA, MX, or NS."SRV"no

Exported fields

The following field is exported and can be referenced by other components:

targetslist(map(string))The set of targets discovered from the docker API.

Each target includes the following labels:

  • __meta_dns_name: Name of the record that produced the discovered target.
  • __meta_dns_srv_record_target: Target field of the SRV record.
  • __meta_dns_srv_record_port: Port field of the SRV record.
  • __meta_dns_mx_record_target: Target field of the MX record.
  • __meta_dns_ns_record_target: Target field of the NS record.

Component health

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

Debug information

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

Debug metrics

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


This example discovers targets from an A record.

discovery.dns "dns_lookup" {
  names = ["", ""]
  type = "A"
  port = 8080

prometheus.scrape "demo" {
  targets    = discovery.dns.dns_lookup.targets
  forward_to = [prometheus.remote_write.demo.receiver]

prometheus.remote_write "demo" {
  endpoint {

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


Connecting some components may not be sensible or components may require further configuration to make the connection work correctly. Refer to the linked documentation for more details.