Grafana dashboards for containers in Docker - Step-by-Step Execution

Process Flow - Grafana dashboards for containers

Start Docker Containers

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Collect Metrics with Prometheus

↓

Grafana Connects to Prometheus

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Create Dashboard in Grafana

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Visualize Container Metrics

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Monitor & Analyze Container Health

This flow shows how container metrics are collected and visualized using Grafana dashboards connected to Prometheus.

Execution Sample

Docker

docker run -d --name prometheus -p 9090:9090 prom/prometheus

docker run -d --name grafana -p 3000:3000 grafana/grafana

# Configure Grafana to use Prometheus as data source
# Import container metrics dashboard

# Access Grafana UI at http://localhost:3000

This code runs Prometheus and Grafana containers, sets up Prometheus as data source, and imports a dashboard to visualize container metrics.

Process Table

Step	Action	Result	System State
1	Run Prometheus container	Prometheus starts on port 9090	Prometheus container running
2	Run Grafana container	Grafana starts on port 3000	Grafana container running
3	Configure Grafana data source	Prometheus added as data source	Grafana connected to Prometheus
4	Import container metrics dashboard	Dashboard loaded with panels	Dashboard ready to display metrics
5	Access Grafana UI	Dashboard visible in browser	User can see container metrics
6	Monitor container metrics	Metrics update in real-time	Continuous monitoring active
7	Stop process	User stops monitoring	Containers can be stopped or kept running

💡 User finishes monitoring or stops containers

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	After Step 5	Final
Prometheus Container	Not running	Running	Running	Running	Running	Running	Running or stopped
Grafana Container	Not running	Not running	Running	Running	Running	Running	Running or stopped
Grafana Data Source	None	None	None	Prometheus	Prometheus	Prometheus	Prometheus
Dashboard	None	None	None	None	Loaded	Loaded	Loaded
User Access	No	No	No	No	No	Yes	Yes

Key Moments - 3 Insights

Why do we need Prometheus before Grafana can show container metrics?

Prometheus collects and stores the container metrics. Grafana only visualizes data from a data source like Prometheus, as shown in step 3 of the execution_table.

What happens if Grafana is running but Prometheus is not?

Grafana cannot display container metrics because it has no data source connected. This is shown in step 2 where Grafana runs but step 3 data source is missing.

How does the dashboard update metrics in real-time?

Grafana queries Prometheus regularly to get fresh metrics, so the dashboard panels update continuously as in step 6.

Visual Quiz - 3 Questions

Look at the execution_table, at which step is Prometheus first running?

A Step 3

B Step 2

C Step 1

D Step 4

💡 Hint

Check the 'Result' column for Prometheus starting.

According to variable_tracker, what is the state of Grafana container after Step 2?

A Not running

B Running

C Stopped

D Unknown

💡 Hint

Look at the 'Grafana Container' row under 'After Step 2' column.

If the data source configuration in Grafana is missing, what will happen to the dashboard?

A Dashboard will load but show no data

B Dashboard will show metrics normally

C Grafana will crash

D Prometheus will stop collecting metrics

💡 Hint

Refer to step 3 and 4 in execution_table and variable_tracker for data source and dashboard state.

Concept Snapshot

Run Prometheus container to collect metrics
Run Grafana container for visualization
Configure Grafana to use Prometheus as data source
Import or create dashboards to display container metrics
Access Grafana UI to monitor containers in real-time

Full Transcript

To monitor containers visually, first run Prometheus in a Docker container to collect metrics. Then run Grafana container to visualize data. Configure Grafana to connect to Prometheus as its data source. Import or create dashboards in Grafana that show container metrics like CPU, memory, and network. Access Grafana's web UI to see live updates and monitor container health easily.

Practice

1. What is the primary purpose of using Grafana dashboards for Docker containers?

easy

A. To write Dockerfiles automatically

B. To visually monitor container health and performance metrics

C. To build Docker images faster

D. To deploy containers without configuration

Solution

1. Step 1: Understand Grafana's role

   Grafana is a tool designed to visualize data, especially metrics and logs.

2. Step 2: Connect Grafana to container metrics

   When connected to data sources like Prometheus, Grafana shows container health and performance visually.

3. Final Answer:

   To visually monitor container health and performance metrics -> Option B

4. Quick Check:

   Grafana = Visual monitoring [OK]

Hint: Grafana = Visual dashboards for metrics [OK]

Common Mistakes:

• Confusing Grafana with image building tools
• Thinking Grafana deploys containers
• Assuming Grafana writes Dockerfiles

2. Which Docker command correctly runs Grafana exposing it on port 3000?

easy

A. docker run -d -p 80:3000 grafana/grafana

B. docker run -d -p 8080:3000 grafana/grafana

C. docker run -d -p 3000:8080 grafana/grafana

D. docker run -d -p 3000:3000 grafana/grafana

Solution

1. Step 1: Identify Grafana default port

   Grafana listens on port 3000 inside the container.

2. Step 2: Map host port 3000 to container port 3000

   The correct syntax is -p hostPort:containerPort, so -p 3000:3000 exposes Grafana on host port 3000.

3. Final Answer:

   docker run -d -p 3000:3000 grafana/grafana -> Option D

4. Quick Check:

   Port mapping = host:container [OK]

Hint: Map host port 3000 to container port 3000 [OK]

Common Mistakes:

• Swapping host and container ports
• Using wrong ports like 8080 or 80
• Not running container in detached mode

3. Given this Docker command, what will happen when you access http://localhost:3000?

docker run -d -p 3000:3000 grafana/grafana

medium

A. You will see the Docker container logs

B. You will get a 404 Not Found error

C. You will see the Grafana login page

D. The browser will fail to connect

Solution

1. Step 1: Understand port mapping

   Port 3000 on localhost is forwarded to Grafana's port 3000 inside the container.

2. Step 2: Accessing localhost:3000 loads Grafana UI

   Grafana serves its web interface on port 3000, so the login page appears.

3. Final Answer:

   You will see the Grafana login page -> Option C

4. Quick Check:

   Port 3000 mapped = Grafana UI loads [OK]

Hint: Port 3000 access shows Grafana login [OK]

Common Mistakes:

• Expecting error pages instead of UI
• Confusing logs with web interface
• Assuming no connection due to missing config

4. You ran Grafana with docker run -d -p 3000:3000 grafana/grafana but cannot access the dashboard at http://localhost:3000. What is a likely cause?

medium

A. Grafana container is not running or crashed

B. You used the wrong image name

C. Port 3000 is not exposed inside the container

D. Docker daemon is not installed

Solution

1. Step 1: Check container status

   If the container stopped or crashed, the port won't be accessible.

2. Step 2: Verify container is running

   Use docker ps to confirm Grafana container is active.

3. Final Answer:

   Grafana container is not running or crashed -> Option A

4. Quick Check:

   Container running = Dashboard accessible [OK]

Hint: Check container status with docker ps [OK]

Common Mistakes:

• Assuming wrong image name without checking
• Thinking port exposure inside container is missing
• Ignoring Docker daemon status

5. You want to monitor multiple Docker containers' CPU and memory usage in Grafana. Which setup step is essential before creating dashboards?

hard

A. Connect Grafana to a metrics data source like Prometheus collecting container stats

B. Install Grafana plugins inside each container

C. Run Grafana with extra CPU and memory limits

D. Expose all container ports to the host

Solution

1. Step 1: Understand Grafana data source role

   Grafana itself does not collect metrics; it visualizes data from sources like Prometheus.

2. Step 2: Set up Prometheus to scrape container metrics

   Prometheus collects CPU and memory stats from Docker containers and provides data to Grafana.

3. Step 3: Connect Grafana to Prometheus

   Configure Grafana to use Prometheus as a data source to build dashboards.

4. Final Answer:

   Connect Grafana to a metrics data source like Prometheus collecting container stats -> Option A

5. Quick Check:

   Data source connection = Dashboard data [OK]

Hint: Grafana needs data source like Prometheus first [OK]

Common Mistakes:

• Thinking Grafana collects metrics alone
• Installing plugins inside containers unnecessarily
• Exposing all ports without reason