How to take backup of docker container ?

In this post, we will look how to take backup of a docker container.

We can take backup in two steps:
a. First saving the container data into an image.
b. Saving the new image into TAR file.

1. Save Container data into an image.

$ docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
phpmyadmin          phpmyadmin          5622104ad36d        22 hours ago        370MB

$ docker ps --all
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
899d5bacbeb1        5622104ad36d        "php_container1"    22 hours ago        Created                                 frosty_panini

$ docker commit -p 899d5bacbeb1 php_container_backup 
sha256:64fb7636f6b9b594d5e6b7f6f3439d177758d4ec84789080e679d791d9bef7e1

2. Save the new image into TAR file.

$ docker images
REPOSITORY             TAG                 IMAGE ID            CREATED             SIZE
php_container_backup   latest              64fb7636f6b9        3 seconds ago       370MB
phpmyadmin             phpmyadmin          5622104ad36d        22 hours ago        370MB

$ docker save 64fb7636f6b9 > /tmp/php_container_backup.tar
$ ls -l /tmp/php_container_backup.tar
-rw-r--r--  1 saket  wheel  378963968 Jan 17 02:21 /tmp/php_container_backup.tar

$ du -sh /tmp/php_container_backup.tar
361M	/tmp/php_container_backup.tar
$ 

Tags: backupcommitcontainerdockerimagelinuxlspssave