Podman

Describes how to run LocalStack inside Podman.

Overview

By default, the LocalStack CLI starts the LocalStack runtime inside a Docker container. Docker may not be available on your system, and a popular alternative is Podman which you can use to run LocalStack. Podman support is still experimental, and the following docs give you an overview of the current state.

From the Podman docs:

Podman is a daemonless, open source, Linux native tool designed to make it easy to find, run, build, share and deploy applications using Open Containers Initiative (OCI) Containers and Container Images. Podman provides a command line interface (CLI) familiar to anyone who has used the Docker Container Engine. Most users can simply alias Docker to Podman (alias docker=podman) without any problems.

Options

To run localstack, simply aliasing alias docker=podman is not enough, for the following reasons:

  • localstack is using docker-py which requires a connection to /var/run/docker.sock
  • LAMBDA_EXECUTOR=docker requires mounting /var/run/docker.sock into the container

Here are several options on running LocalStack using podman:

podman-docker

The package podman-docker emulates the Docker CLI using podman. It creates the following links:

  • /usr/bin/docker -> /usr/bin/podman
  • /var/run/docker.sock -> /run/podman/podman.sock

This package is available for some distros:

Rootfull Podman with podman-docker

The simplest option is to run localstack using podman by having podman-docker and running localstack start as root

  1. # you have to start the podman socket first
  2. sudo systemctl start podman
  3. # then
  4. sudo sh -c 'DEBUG=1 localstack start'

Rootfull Podman without podman-docker

  1. # you still have to start the podman socket first
  2. sudo systemctl start podman
  3. # you have to pass a bunch of env variables
  4. sudo sh -c 'DEBUG=1 DOCKER_CMD=podman DOCKER_HOST=unix://run/podman/podman.sock DOCKER_SOCK=/run/podman/podman.sock localstack start'

Rootless Podman

You have to prepare your environment first:

  1. # again, you have to start the podman socket first
  2. systemctl --user start podman.service
  3. # and then localstack
  4. DEBUG=1 DOCKER_CMD="podman" DOCKER_SOCK=$XDG_RUNTIME_DIR/podman/podman.sock DOCKER_HOST=unix://$XDG_RUNTIME_DIR/podman/podman.sock localstack start

If you have problems with subuid and subgid, you could try to use overlay.ignore_chown_errors option

  1. DEBUG=1 DOCKER_CMD="podman --storage-opt overlay.ignore_chown_errors=true" DOCKER_SOCK=$XDG_RUNTIME_DIR/podman/podman.sock DOCKER_HOST=unix://$XDG_RUNTIME_DIR/podman/podman.sock localstack start

Last modified January 6, 2022: add documentation updates for ElastiCache, Podman, CloudFormation (#102) (2119b38b)