The Datadog Agent can create and assign tags to all metrics, traces, and logs emitted by a container based on its labels or environment variables.
If you are running the Agent as a binary on a host, configure your tag extractions with the Agent tab instructions. If you are running the Agent as a container, configure your tag extraction with the Containerized Agent tab instructions.
The Agent can autodiscover and attach tags to all data emitted by containers. The list of tags attached depends on the Agent cardinality configuration.
| Tag | Cardinality | Requirement |
|---|---|---|
container_name | High | N/A |
container_id | High | N/A |
rancher_container | High | Rancher environment |
mesos_task | Orchestrator | Mesos environment |
docker_image | Low | N/A |
image_name | Low | N/A |
short_image | Low | N/A |
image_tag | Low | N/A |
swarm_service | Low | Swarm environment |
swarm_namespace | Low | Swarm environment |
rancher_stack | Low | Rancher environment |
rancher_service | Low | Rancher environment |
env | Low | Unified service tagging enabled |
version | Low | Unified service tagging enabled |
service | Low | Unified service tagging enabled |
marathon_app | Low | Marathon environment |
chronos_job | Low | Mesos environment |
chronos_job_owner | Low | Mesos environment |
nomad_task | Low | Nomad environment |
nomad_job | Low | Nomad environment |
nomad_group | Low | Nomad environment |
As a best practice in containerized environments, Datadog recommends using unified service tagging when assigning tags. Unified service tagging ties Datadog telemetry together through the use of three standard tags: env, service, and version. To learn how to configure your environment with unified tagging, see the dedicated unified service tagging documentation.
Starting with Agent v6.0+, the Agent can collect labels for a given container and use them as tags to attach to all data emitted by this container.
To extract a given Docker label <LABEL_NAME> and transform it as a tag key <TAG_KEY> within Datadog, add the following environment variable to the Datadog Agent:
DD_DOCKER_LABELS_AS_TAGS='{"<LABEL_NAME>": "<TAG_KEY>"}'
For example, you could set up:
DD_DOCKER_LABELS_AS_TAGS='{"com.docker.compose.service":"service_name"}'
Note: <LABEL_NAME> is not case-sensitive. For example, if you have labels named foo and FOO, and you set DD_DOCKER_LABELS_AS_TAGS='{"foo": "bar"}', both foo and FOO are mapped to bar.
To extract a given Docker label <LABEL_NAME> and transform it as a tag key <TAG_KEY> within Datadog, add the following configuration block in the Agent datadog.yaml configuration file:
docker_labels_as_tags:
<LABEL_NAME>: <TAG_KEY>
For example, you could set up:
docker_labels_as_tags:
com.docker.compose.service: service_name
Datadog automatically collects common tags from Docker, Kubernetes, ECS, Swarm, Mesos, Nomad, and Rancher. To extract even more tags, use the following options:
| Environment Variable | Description |
|---|---|
DD_DOCKER_LABELS_AS_TAGS | Extract docker container labels |
DD_DOCKER_ENV_AS_TAGS | Extract docker container environment variables |
DD_KUBERNETES_POD_LABELS_AS_TAGS | Extract pod labels |
DD_CHECKS_TAG_CARDINALITY | Add tags to check metrics |
DD_DOGSTATSD_TAG_CARDINALITY | Add tags to custom metrics |
Starting with Agent v7.20+, a containerized Agent can Autodiscover tags from Docker labels. This process allows the Agent to associate custom tags to all data emitted by a container without modifying the Agent datadog.yaml file.
Tags should be added using the following format:
com.datadoghq.ad.tags: '["<TAG_KEY_1>:<TAG_VALUE_1>", "<TAG_KEY_2>:<TAG_VALUE_2>"]'
With Agent v6.0+, the Agent can collect environment variables for a given container and use them as tags to attach to all data emitted by this container.
To extract a given Docker environment variable <ENVVAR_NAME> and transform it as a tag key <TAG_KEY> within Datadog, add the following environment variable to the Datadog Agent:
DD_DOCKER_ENV_AS_TAGS='{"<ENVVAR_NAME>": "<TAG_KEY>"}'
For example, you could set up:
DD_DOCKER_ENV_AS_TAGS='{"ENVIRONMENT":"env"}'
To extract a given Docker environment variable <ENVVAR_NAME> and transform it as a tag key <TAG_KEY> within Datadog, add the following configuration block in the Agent datadog.yaml configuration file:
docker_env_as_tags:
<ENVVAR_NAME>: <TAG_KEY>
For example, you could set up:
docker_env_as_tags:
ENVIRONMENT: env
Additional helpful documentation, links, and articles:
