How to Save and Load Docker Images to Offline Servers

In this post, we’ll see how to make Docker images available to servers that don’t have access to the Internet (i.e., machines where docker pull <image_name> does not work).

As a specific example, we will do this with the latest Percona Monitoring and Management Docker images, since we had requests for this from users and customers. With the following steps, you’ll be able to deploy PMM within your secure network, without access to the Internet. Additionally, the same steps can be used when you need to upgrade the containers’ version in future releases.

There are two ways in which we can do this:

• the easy way, by using docker save and docker load, or
• the not-so-easy way, by setting up our own registry

We’ll focus on the first option since the latter is a bit more convoluted. If you need your own registry, you are probably looking into something else rather than simply avoiding a firewall to pull one image to a server. Check out the Docker online docs in case option two fits your needs better.

As of this writing, 1.1.3 is the latest PMM version, so this is what we’ll use in the example. An image name is comprised of three parts, namely:

• user_account/ (note the ‘/’ at the end); or empty string (and no ‘/’) for the official Docker repo
• image_name
• :tag (note the ‘:’ at the beginning)

The PMM Docker images have the following syntax: percona/pmm-server:1.1.3, but you can change this in the following examples to whatever image name you want, and it will work just the same. Before moving on to the commands needed, let’s imagine that serverA is the machine that has access to the Internet and serverB is the machine behind the firewall.

The steps are simple enough. On serverA, get the image, and save it to a file:

Now, all you need to do is move the generated tar file to serverB (by using “scp” or any other means), and execute the following:

Now you’ll be able to use the image as if you had used docker pull percona/pmm-server:1.1.3​:

Lastly, let me add the relevant documentation links, so you have them at hand if needed:

https://www.percona.com/doc/percona-monitoring-and-management/deploy/server/docker.html

https://docs.docker.com/engine/reference/commandline/save/

https://docs.docker.com/engine/reference/commandline/load/