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Docker info|version Command

Docker info command

The docker info command provides system-wide information about your Docker installation, including the number of containers and images, the state of the Docker daemon, and more. This tutorial will guide you through the basics of using the docker info command.

Prerequisites:
- Install Docker on your system
Display Docker information:
To display information about your Docker installation, run:
```
docker info
```
This will display various information about your Docker installation, including:
- The Docker version and build information.
- The number of containers and images.
- The storage driver in use.
- The default runtime (e.g., runc).
- Networking and firewall information.
- The total CPU, memory, and swap available on the system.
- Security options, such as AppArmor, SELinux, or Seccomp.
- Operating system and kernel information.
- And more.
Format the output:
By default, the docker info command displays the information in a human-readable format. If you want to change the output format, you can use the --format or -f flag followed by a Go template string.
For example, to display only the number of running containers, use:
```
docker info --format '{{.ContainersRunning}}'
```
This will display the number of running containers as an integer.
Display Docker info in JSON format:
If you want to display the Docker information in JSON format, use the --format flag with a JSON-compatible Go template:
```
docker info --format '{{json .}}'
```
This will display the Docker information as a JSON object, which can be easily parsed or processed by other tools.

In this tutorial, we covered the basics of using the docker info command to display system-wide information about your Docker installation. The docker info command provides valuable insights into the state of your Docker environment, including container and image counts, storage and networking details, security options, and more. Additionally, by formatting the output and using JSON output, you can tailor the information to your specific needs and integrate it with other tools.

How to Use Docker Info Command:
- Description: The docker info command provides detailed information about the Docker system, including configuration, resources, and networking.
- Code Example:
```
docker info
```
Viewing System Information with Docker Info:
- Description: Docker info offers a comprehensive overview of the Docker environment, including the number of containers, images, and system resources.
- Code Example:
```
docker info
```
Docker Info Command Output Explained:
- Description: Docker info output includes details about the Docker daemon, containers, images, storage, and networking.
- Code Example:
```
docker info
```
Docker Info vs Docker Version:
- Description: While docker info provides detailed system information, docker version focuses on the Docker client and server version details.
- Code Example:
```
docker version
```
Monitoring Resources with Docker Info:
- Description: Docker info includes resource-related metrics, such as the number of CPUs, memory usage, and storage driver details.
- Code Example:
```
docker info
```
Docker Info and Container Statistics:
- Description: Docker info provides a high-level overview of container statistics, including the number of running containers and their states.
- Code Example:
```
docker info
```
Docker Info and Daemon Configuration:
- Description: Get insights into the Docker daemon's configuration, including storage driver, logging options, and more.
- Code Example:
```
docker info
```
Security Considerations with Docker Info:
- Description: Be cautious when sharing the output of docker info, as it contains information about the Docker environment and its configuration.
- Code Example:
```
docker info
```
Docker Info and Swarm Mode:
- Description: In a Docker Swarm mode, docker info provides additional information about the swarm, nodes, and services.
- Code Example:
```
docker info
```
Docker Info and Networking Details:
- Description: Docker info includes information about the networking configuration, such as the number of networks and their types.
- Code Example:
```
docker info
```
Automating System Checks with Docker Info:
- Description: Use docker info in automated scripts or monitoring tools to periodically check the Docker environment's health and status.
- Code Example:
```
# Example script
#!/bin/bash
docker info > docker_info_output.txt
```
Troubleshooting with Docker Info:
- Description: Docker info is a valuable tool for troubleshooting Docker-related issues, providing insights into the system configuration.
- Code Example:
```
docker info
```
Docker Info Command Options and Flags:
- Description: Docker info has no specific options or flags. It is invoked as a standalone command to display system information.
- Code Example:
```
docker info
```
Interpreting Docker Info Metrics:
- Description: Understand the various metrics and information provided by docker info to gain insights into the Docker environment's state.
- Code Example:
```
docker info
```