Airflow metrics with Prometheus - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Airflow Metrics Export

Which Airflow component is responsible for exposing metrics to Prometheus?

A The Airflow Scheduler exposes metrics via a built-in Prometheus exporter.

B The Airflow Worker pushes metrics directly to Prometheus using a push gateway.

C The Airflow Webserver exposes metrics through a Prometheus endpoint.

D The Airflow Metadata Database exports metrics to Prometheus automatically.

💡 Hint

Think about which Airflow service handles HTTP requests and UI.

The Airflow Webserver exposes metrics on a Prometheus endpoint, allowing Prometheus to scrape metrics. The Scheduler and Workers do not expose metrics directly, and the Metadata Database does not export metrics.

💻 Command Output

intermediate

Prometheus Metrics Endpoint Output

What is the expected output when you curl the Airflow Webserver's Prometheus metrics endpoint /metrics?

Apache Airflow

curl http://localhost:8080/metrics

A

# HELP airflow_scheduler_heartbeat_seconds Time since last scheduler heartbeat
# TYPE airflow_scheduler_heartbeat_seconds gauge
airflow_scheduler_heartbeat_seconds 12.345

B

# HELP airflow_task_duration_seconds Duration of task execution
# TYPE airflow_task_duration_seconds histogram
airflow_task_duration_seconds_bucket{le="5"} 10
airflow_task_duration_seconds_bucket{le="10"} 15

C

HTTP 404 Not Found

D

Error: Connection refused

💡 Hint

The metrics endpoint provides Prometheus formatted metrics about Airflow components.

The Airflow Webserver's /metrics endpoint exposes metrics like scheduler heartbeat as gauges. Option A shows a valid Prometheus metric output. Option A is a 404 error which means the endpoint is missing. Option A shows task duration histogram which is not exposed by default. Option A is a connection error.

❓ Configuration

advanced

Configuring Airflow to Enable Prometheus Metrics

Which configuration change is required in airflow.cfg to enable Prometheus metrics on the Airflow Webserver?

A

[metrics]
prometheus = True
port = 9090

B

[metrics]
enabled = True
exporter = prometheus

C

[webserver]
metrics_exporter = prometheus
metrics_port = 8080

D

[metrics]
enabled = True
backend = prometheus

💡 Hint

Look for the correct section and keys related to metrics export.

The correct configuration to enable Prometheus metrics is under the [metrics] section with keys 'enabled = True' and 'exporter = prometheus'. Other options either use wrong keys or sections.

❓ Troubleshoot

advanced

Troubleshooting Missing Metrics in Prometheus

You configured Airflow to expose Prometheus metrics, but Prometheus shows no data for Airflow targets. What is the most likely cause?

A The Airflow Webserver is not running or not reachable on the metrics port.

B Prometheus is not configured to scrape the Airflow Metadata Database.

C The Airflow Scheduler is not pushing metrics to Prometheus push gateway.

D The Airflow Workers are blocking the metrics endpoint with firewall rules.

💡 Hint

Check network connectivity and service status first.

If Prometheus shows no data, the most common cause is that the Airflow Webserver is down or unreachable on the metrics port. Prometheus scrapes the Webserver, not the Metadata DB or Workers. Airflow does not push metrics to a push gateway by default.

🔀 Workflow

expert

Setting Up Full Airflow Metrics Monitoring with Prometheus and Grafana

Order the steps correctly to set up Airflow metrics monitoring with Prometheus and Grafana.

A 1,3,2,4

B 2,1,3,4

C 3,2,1,4

D 1,2,3,4

💡 Hint

Think about enabling metrics first, then scraping, then visualization setup.

First, enable metrics in Airflow and restart the Webserver. Second, configure Prometheus to scrape those metrics. Third, deploy Grafana and add Prometheus as data source. Finally, import or create dashboards to visualize the metrics.