service · inferred from evidence
APM
Application Performance Monitoring, referenced in the context of grouping services by env and version.
- Datadog on ECS: one agent per EC2 host as a daemon service, Fargate is a separate setup
ECS on EC2: run one Datadog agent container per EC2 host as a daemon service task definition. ECS on Fargate is a different integration with its own docs page. Not the full reference manual.
- APM trace agent connection refused: point the tracer at the agent with DD_AGENT_HOST
Tracers ship to the Datadog agent on the same host by default. Connection refused means the tracer cannot reach it: wrong DD_AGENT_HOST in containers, agent APM not enabled, or a firewall in between.