--- title: "discovery.consul | Grafana Agent documentation" description: "Learn about discovery.consul" --- # discovery.consul `discovery.consul` allows retrieving scrape targets from [Consul’s Catalog API](https://www.consul.io/use-cases/discover-services). ## Usage Alloy ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```alloy discovery.consul "LABEL" { server = CONSUL_SERVER } ``` ## Arguments The following arguments are supported: Expand table | Name | Type | Description | Default | Required | |--------------------------|---------------------|---------------------------------------------------------------------------------------------------------------------------------------------|------------------|----------| | `server` | `string` | Host and port of the Consul API. | `localhost:8500` | no | | `token` | `secret` | Secret token used to access the Consul API. | | no | | `datacenter` | `string` | Datacenter to query. If not provided, the default is used. | | no | | `namespace` | `string` | Namespace to use (only supported in Consul Enterprise). | | no | | `partition` | `string` | Admin partition to use (only supported in Consul Enterprise). | | no | | `tag_separator` | `string` | The string by which Consul tags are joined into the tag label. | `,` | no | | `scheme` | `string` | The scheme to use when talking to Consul. | `http` | no | | `username` | `string` | The username to use (deprecated in favor of the basic\_auth configuration). | | no | | `password` | `secret` | The password to use (deprecated in favor of the basic\_auth configuration). | | no | | `allow_stale` | `bool` | Allow stale Consul results (see [official documentation](https://www.consul.io/api/features/consistency.html)). Will reduce load on Consul. | `true` | no | | `services` | `list(string)` | A list of services for which targets are retrieved. If omitted, all services are scraped. | | no | | `tags` | `list(string)` | An optional list of tags used to filter nodes for a given service. Services must contain all tags in the list. | | no | | `node_meta` | `map(string)` | Node metadata key/value pairs to filter nodes for a given service. | | no | | `refresh_interval` | `duration` | Frequency to refresh list of containers. | `"30s"` | no | | `bearer_token_file` | `string` | File containing a bearer token to authenticate with. | | no | | `bearer_token` | `secret` | Bearer token to authenticate with. | | no | | `enable_http2` | `bool` | Whether HTTP2 is supported for requests. | `true` | no | | `follow_redirects` | `bool` | Whether redirects returned by the server should be followed. | `true` | no | | `proxy_url` | `string` | HTTP proxy to send requests through. | | no | | `no_proxy` | `string` | Comma-separated list of IP addresses, CIDR notations, and domain names to exclude from proxying. | | no | | `proxy_from_environment` | `bool` | Use the proxy URL indicated by environment variables. | `false` | no | | `proxy_connect_header` | `map(list(secret))` | Specifies headers to send to proxies during CONNECT requests. | | no | At most, one of the following can be provided: - [`bearer_token` argument](#arguments). - [`bearer_token_file` argument](#arguments). - [`basic_auth` block](#basic_auth-block). - [`authorization` block](#authorization-block). - [`oauth2` 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.consul`: Expand table | Hierarchy | Block | Description | Required | |-------------------------|---------------------------------------|-----------------------------------------------------------|----------| | basic\_auth | [basic\_auth](#basic_auth-block) | Configure basic\_auth for authenticating to the endpoint. | no | | authorization | [authorization](#authorization-block) | Configure generic authorization to the endpoint. | no | | oauth2 | [oauth2](#oauth2-block) | Configure OAuth2 for authenticating to the endpoint. | no | | oauth2 > tls\_config | [tls\_config](#tls_config-block) | Configure TLS settings for connecting to the endpoint. | no | | tls\_config | [tls\_config](#tls_config-block) | Configure TLS settings for connecting to the endpoint. | no | 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 Expand table | Name | Type | Description | Default | Required | |-----------------|----------|------------------------------------------|---------|----------| | `password_file` | `string` | File containing the basic auth password. | | no | | `password` | `secret` | Basic auth password. | | no | | `username` | `string` | Basic auth username. | | no | `password` and `password_file` are mutually exclusive, and only one can be provided inside a `basic_auth` block. ### authorization block Expand table | Name | Type | Description | Default | Required | |--------------------|----------|--------------------------------------------|---------|----------| | `credentials_file` | `string` | File containing the secret value. | | no | | `credentials` | `secret` | Secret value. | | no | | `type` | `string` | Authorization type, for example, “Bearer”. | | no | `credential` and `credentials_file` are mutually exclusive, and only one can be provided inside an `authorization` block. ### oauth2 block Expand table | Name | Type | Description | Default | Required | |--------------------------|---------------------|--------------------------------------------------------------------------------------------------|---------|----------| | `client_id` | `string` | OAuth2 client ID. | | no | | `client_secret_file` | `string` | File containing the OAuth2 client secret. | | no | | `client_secret` | `secret` | OAuth2 client secret. | | no | | `endpoint_params` | `map(string)` | Optional parameters to append to the token URL. | | no | | `proxy_url` | `string` | HTTP proxy to send requests through. | | no | | `no_proxy` | `string` | Comma-separated list of IP addresses, CIDR notations, and domain names to exclude from proxying. | | no | | `proxy_from_environment` | `bool` | Use the proxy URL indicated by environment variables. | `false` | no | | `proxy_connect_header` | `map(list(secret))` | Specifies headers to send to proxies during CONNECT requests. | | no | | `scopes` | `list(string)` | List of scopes to authenticate with. | | no | | `token_url` | `string` | URL to fetch the token from. | | no | `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 Expand table | Name | Type | Description | Default | Required | |------------------------|----------|----------------------------------------------------------|---------|----------| | `ca_pem` | `string` | CA PEM-encoded text to validate the server with. | | no | | `ca_file` | `string` | CA certificate to validate the server with. | | no | | `cert_pem` | `string` | Certificate PEM-encoded text for client authentication. | | no | | `cert_file` | `string` | Certificate file for client authentication. | | no | | `insecure_skip_verify` | `bool` | Disables validation of the server certificate. | | no | | `key_file` | `string` | Key file for client authentication. | | no | | `key_pem` | `secret` | Key PEM-encoded text for client authentication. | | no | | `min_version` | `string` | Minimum acceptable TLS version. | | no | | `server_name` | `string` | ServerName extension to indicate the name of the server. | | no | 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: Expand table | Name | Type | Description | |-----------|---------------------|------------------------------------------------------------| | `targets` | `list(map(string))` | The set of targets discovered from the Consul catalog API. | Each target includes the following labels: - `__meta_consul_address`: the address of the target. - `__meta_consul_dc`: the datacenter name for the target. - `__meta_consul_health`: the health status of the service. - `__meta_consul_partition`: the admin partition name where the service is registered. - `__meta_consul_metadata_`: each node metadata key value of the target. - `__meta_consul_node`: the node name defined for the target. - `__meta_consul_service_address`: the service address of the target. - `__meta_consul_service_id`: the service ID of the target. - `__meta_consul_service_metadata_`: each service metadata key value of the target. - `__meta_consul_service_port`: the service port of the target. - `__meta_consul_service`: the name of the service the target belongs to. - `__meta_consul_tagged_address_`: each node tagged address key value of the target. - `__meta_consul_tags`: the list of tags of the target joined by the tag separator. ## Component health `discovery.consul` is only reported as unhealthy when given an invalid configuration. In those cases, exported fields retain their last healthy values. ## Debug information `discovery.consul` does not expose any component-specific debug information. ## Debug metrics `discovery.consul` does not expose any component-specific debug metrics. ## Example This example discovers targets from Consul for the specified list of services: Alloy ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy ```alloy discovery.consul "example" { server = "localhost:8500" services = [ "service1", "service2", ] } prometheus.scrape "demo" { targets = discovery.consul.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.consul` has exports that can be consumed by the following components: - Components that consume [Targets](../../compatibility/#targets-consumers) > Note > > 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.