Docker runtime

Run commands inside a container image using Docker.

Docker is a very popular container system freely-available for all platforms. When you use Docker with the Nextstrain CLI, you don’t need to install any other Nextstrain software dependencies as validated versions are already bundled into a container image (nextstrain/base) by the Nextstrain team.

Setup

Hint

This is a reference page with brief pointers for set up. For a more comprehensive installation guide, please see our general Nextstrain installation page.

On macOS, download and install Docker Desktop, also known previously as “Docker for Mac”.

On Linux, install Docker with the standard package manager. For example, on Ubuntu, you can install Docker with sudo apt install docker.io.

On Windows, install Docker Desktop with its support for a WSL2 backend.

Once you’ve installed Docker, proceed with nextstrain setup docker.

This will download compressed image layers totaling about 750 MB in size which expand to a final on-disk size of about 2 GB. Transient disk usage during this process peaks at about 3 GB. These numbers are current as of August 2023, as observed on Linux. Numbers will vary over time, with a tendency to slowly increase, and vary slightly by OS.

Config file variables

Defaults for the corresponding command line options, specified in the config file.

docker.image

Default for --image when using the Docker runtime, e.g. nextstrain/base:build-20230623T174208Z.

Typically set initially by nextstrain setup and subsequently by nextstrain update.

Environment variables

Warning

For development only. You don’t need to set these during normal operation.

Defaults for the corresponding command line options, potentially overriding defaults set by config file variables.

NEXTSTRAIN_DOCKER_IMAGE

Default for --image when using the Docker runtime.