FAQ about Dev Containers

After a Dev Container is created, the following volumes and properties appear in Docker:

• jb_devcontainers_shared_volume: the process of copying an IDE backend takes a certain amount of time. However, this process is done only once during the first Dev Container creation, and everything is copied into this volume. Then, this volume is shared among multiple containers, and we don't need to repeat the downloading process. If we create a Dev Container using another IDE or a different IDE version, we copy it into the same Docker volume. All backends are stored in one volume, making it easy to manage.

  For example, remove unnecessary backends through the Manage backends dialog.

• jb-devcontainer-features-xxx: if you use features in your devcontainer.json file then all features are placed into such images.

  Currently, the unnecessary images should be deleted manually.

• jb_devcontainer_sources_xxx: if we use git clone then all sources are cloned into this volume using helper container (based on alpine/git image).

Add to Help | Diagnostic Tools | Debug Log Settings the following strings:

com.intellij.platform.ijent:all

com.intellij.clouds.docker.gateway.ijent:all

Run the following command:

docker --host <ssh> build <git-url>:<context-dir>

Check the following example:

docker --host ssh://jetbrains@MUNIT-234:22 build
            git@git.jetbrains.team/devcont/DevCont_test_cases.git:.devcontainer

We create a helper container based on the small alpine/git image, which contains some of the required tools or libraries, for example, Git or the SSH client. We need that to clone the repository that can be absent in the image used for a Dev Container creation.

If we already have all the sources locally, there is no need to use such a complicated and slow method like Docker via SSH.

You can build a Dev Container for a project with the .json file that resides on the remote backend.

For more information, refer to Start Dev Container for a remote project.

The local Docker collects the correct context and clones only the necessary files into a Dev Container instead of the entire repository, which can be quite large.

The local Docker CLI is required for the current implementation to collect the correct context and clone only the necessary files into the remote machine. You can check requirements in the Prerequisites for working with Docker on a remote server section.

note

In terms of the Docker plugin, running Dockerfile and Docker Compose configurations on a remote machine requires the local Docker CLI. Building a Dev Container on a remote Docker Engine also needs the local Docker CLI. However, note that the Image run configurations don't have this requirement.