Overview
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.
Out-of-the-box tagging
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
Note: not included for the containerd runtime. |
container_id | High | N/A |
rancher_container | High | Rancher environment |
mesos_task | Orchestrator | Mesos environment |
docker_image | Low | N/A
Note: not included for the containerd runtime. |
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 |
git.commit.sha | Low | org.opencontainers.image.revision used |
git.repository_url | Low | org.opencontainers.image.source used |
Unified service tagging
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 container label <LABEL_NAME> and transform it as a tag key <TAG_KEY> within Datadog, add the following environment variable to the Datadog Agent:
DD_CONTAINER_LABELS_AS_TAGS='{"<LABEL_NAME>":"<TAG_KEY>"}'
For example, you could set up:
DD_CONTAINER_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_CONTAINER_LABELS_AS_TAGS='{"foo": "bar"}', both foo and FOO are mapped to bar.
Note: DD_CONTAINER_LABELS_AS_TAGS is equivalent to the old DD_DOCKER_LABELS_AS_TAGS, and DD_CONTAINER_ENV_AS_TAGS to DD_DOCKER_ENV_AS_TAGS.
To extract a given container 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:
container_labels_as_tags:
<LABEL_NAME>: <TAG_KEY>
For example, you could set up:
container_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_CONTAINER_LABELS_AS_TAGS | Extract container labels |
DD_CONTAINER_ENV_AS_TAGS | Extract 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 container 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 container 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_CONTAINER_ENV_AS_TAGS='{"<ENVVAR_NAME>": "<TAG_KEY>"}'
For example, you could set up:
DD_CONTAINER_ENV_AS_TAGS='{"ENVIRONMENT":"env"}'
To extract a given container 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:
container_env_as_tags:
<ENVVAR_NAME>: <TAG_KEY>
For example, you could set up:
container_env_as_tags:
ENVIRONMENT: env
Further Reading
Additional helpful documentation, links, and articles:
