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discovery.consulagent
discovery.consulagent
allows you to retrieve scrape targets from Consul’s Agent API.
Only the services registered with the local agent running on the same host will be watched.
This is suitable for very large Consul clusters for which using the Catalog API would be too slow or resource intensive.
Usage
discovery.consulagent "LABEL" {
server = CONSUL_SERVER
}
Arguments
The following arguments are supported:
Name | Type | Description | Default | Required |
---|---|---|---|---|
server | string | Host and port of the Consul Agent API. | localhost:8500 | no |
token | secret | Secret token used to access the Consul Agent API. | no | |
datacenter | string | Datacenter in which the Consul Agent is configured to run. If not provided, the datacenter is retrieved from the local Consul Agent. | 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 the Consul Agent. | http | no |
username | string | The username to use. | no | |
password | secret | The password to use. | 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 | |
refresh_interval | duration | Frequency to refresh list of containers. | "30s" | no |
Blocks
The following blocks are supported inside the definition of
discovery.consulagent
:
Hierarchy | Block | Description | Required |
---|---|---|---|
tls_config | tls_config | Configure TLS settings for connecting to the endpoint. | no |
tls_config block
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
andca_file
cert_pem
andcert_file
key_pem
andkey_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:
Name | Type | Description |
---|---|---|
targets | list(map(string)) | The set of targets discovered from the Consul Agent API. |
Each target includes the following labels:
__meta_consulagent_address
: The address of the target.__meta_consulagent_dc
: The datacenter name for the target.__meta_consulagent_health
: The health status of the service.__meta_consulagent_metadata_<key>
: Each node metadata key value of the target.__meta_consulagent_node
: The node name defined for the target.__meta_consulagent_service
: The name of the service the target belongs to.__meta_consulagent_service_address
: The service address of the target.__meta_consulagent_service_id
: The service ID of the target.__meta_consulagent_service_metadata_<key>
: Each service metadata key value of the target.__meta_consulagent_service_port
: The service port of the target.__meta_consulagent_tagged_address_<key>
: Each node tagged address key value of the target.__meta_consulagent_tags
: The list of tags of the target joined by the tag separator.
Component health
discovery.consulagent
is only reported as unhealthy when given an invalid configuration.
In those cases, exported fields retain their last healthy values.
Debug information
discovery.consulagent
doesn’t expose any component-specific debug information.
Debug metrics
discovery_consulagent_rpc_failures_total
(Counter): The number of Consul Agent RPC call failures.discovery_consulagent_rpc_duration_seconds
(SummaryVec): The duration of a Consul Agent RPC call in seconds.
Example
This example discovers targets from a Consul Agent for the specified list of services:
discovery.consulagent "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.consulagent
has exports that can be consumed by the following components:
- Components that consume Targets
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.