Here, you will learn how to backup and restore a Docker container locally – an alternative approach to push and pull the container from Docker Hub.
If you need to learn the basics of Docker, please check this other tutorial.
1. Why Should You Care about Backuping a Docker Container?
There are several reasons why you should care about backing up a Docker container:
- Data Protection: Docker containers often store important data, such as database records, user information, and application configurations. By backing up this data, you can ensure that it is protected in case of data loss or corruption.
- Disaster Recovery: Backing up Docker containers can help you quickly recover from disaster scenarios, such as server crashes or data center outages. With a backup, you can easily restore the data and applications stored in a Docker container.
- Version Control: Backing up Docker containers can help you maintain version control over your applications and data. By taking regular backups, you can easily revert to previous versions of your container if necessary.
- Reproducibility: Backing up Docker containers can help you reproduce a particular state of your applications and data. This can be useful when testing or debugging applications.
- Security: Backing up Docker containers can help you secure your data by keeping a copy of it in a secure location. This can protect against unauthorized access, theft, or other security threats.
Overall, backing up Docker containers is an important part of a comprehensive data management strategy. By taking regular backups, you can ensure that your data is protected and that you can quickly recover from unexpected events.
2. How to Backup a Docker Container
Backing up a Docker container is a 4 step process:
First, the user needs to run the docker image by using the command below:
$ docker run -it IMAGE_ID
where the IMAGE_ID should be the image you want to backup; find it using the command docker images
Now you have got it running, please open another tab in your terminal, and figure out the running container ID associated with the image above by running:
$ sudo docker container ls
Next, you know which running container to backup, run the command below using the CONTAINER_ID
$ sudo docker commit -p CONTAINER_ID my_backup
The command above commits the container, and finally, the command below will backup the container into a tar file:
$ sudo docker save -o my_backup.tar my_backup
3. How to Restore a Docker Container
Phew! Now that you know how to backup a container, restoring it should be straightforward using the command below:
$ sudo docker load -i my_backup.tar
Last but not least, the command loads the docker image and can be seen when running the command docker images and execute using docker run -it IMAGE_ID
This tutorial teaches an alternative approach to push and pull a container from Docker Hub, and using the step-by-step described here; the user can back it up locally and restore it when desired.