Deployment

Deploying the application is straightforward. Once you've completed the configuration, use the following steps to start and verify the application. Additional debugging options are provided to help troubleshoot any issues during deployment.

Steps to Deploy the Application¶

1. Start the Application

Run the following command to start all services in detached mode:

Bash

docker compose up -d

After executing this command, you may see some warning messages. These messages are not critical and can be safely ignored.

2. Verify Container Status

Check the status of all containers to ensure they are running and healthy. The all applications will be healty about 3-4 minutes:

Bash

docker ps

If the process takes longer than 5 minutes, it may indicate that your CPU does not meet the minimum performance requirements.

Look for the STATUS column. All containers should display healthy or running.
If any container shows unhealthy, proceed to the debugging steps below.

Warnings and Important Notes¶

Before proceeding with the application deployment, please review the following warnings and notes to ensure a smooth and error-free process.

Missing Environment Variables¶

When running Docker Compose, you might encounter warnings similar to the following:

Text Only

The "EXTERNAL_LOG_PATH" variable is not set. Defaulting to a blank string.
The "DT_LOG_PATH_NAME" variable is not set. Defaulting to a blank string.

These warnings indicate that certain environment variables referenced in the docker-compose.yml file are not defined. By default, Docker Compose assigns an empty string to these variables.

In most cases, these warnings can be safely ignored, as these variables are intentionally left blank. These values are designed to remain unset unless explicitly required by your application. If the related connections or configurations are working successfully, there is no need to modify these variables or address these warnings.

Debugging Options¶

If you encounter issues during deployment, use the following commands to identify and resolve problems:

1. View Global Logs¶

To view logs from all containers managed by the docker-compose.yml file:

Bash

docker compose logs

2. Monitor Resource Usage¶

To monitor resource usage (CPU, memory, etc.) for all running containers:

Bash

docker stats

This is particularly useful for identifying containers that are consuming excessive resources.

3. View Specific Container Logs¶

To view logs for a specific container, use the following command:

Bash

docker logs -f <container_name>

- Replace <container_name> with the name or ID of the container (e.g., backend, frontend, database). - The -f option allows you to follow the logs in real time.

4. Restart a Specific Container¶

If a container is not responding or is in an unhealthy state, restart it:

Bash

docker restart <container_name>

5. Check Container Health Status¶

Inspect the health status of a specific container to understand why it might be unhealthy:

Bash

docker inspect --format='{{json .State.Health}}' <container_name>

6. Check Docker Compose Configuration¶

Validate the docker-compose.yml file to ensure there are no syntax errors:

Bash

docker compose config

7. Stop and Remove Containers (if needed)¶

If you need to stop and completely remove all containers (e.g., to clean up before redeployment):

Bash

docker compose down -v

Example Debugging Workflow¶

Start the application:
Bash
```
docker compose up -d
```
Verify container status:
Bash
```
docker ps
```
Check logs for errors:
- View global logs:
  Bash
```
docker compose logs
```
- View logs for a specific container:
  Bash
```
docker logs -f <container_name>
```
Monitor resource usage:
Bash
```
docker stats
```
Restart an unhealthy container:
Bash
```
docker restart <container_name>
```

Inspect health status:

Bash

docker inspect --format='{{json .State.Health}}' <container_name>

Rebuild and restart containers (if necessary):
Bash
```
docker compose up -d --build
```

Notes¶

Health Checks: Ensure that health checks are correctly configured in the docker-compose.yml file for all services. This helps Docker determine the health status of containers.
Container Names: Use docker ps to list all running containers and identify their names or IDs.