FROM ubuntu:22.04 ARG TAILSCALE_VERSION=* ARG TAILSCALE_CHANNEL=stable RUN apt-get update \ && apt-get install -y gnupg curl ssh dnsutils ca-certificates \ && adduser --shell=/bin/bash ssh-it-user # Tailscale is deliberately split into a second stage so we can cash utils as a seperate layer. RUN curl -fsSL https://pkgs.tailscale.com/${TAILSCALE_CHANNEL}/ubuntu/focal.gpg | apt-key add - \ && curl -fsSL https://pkgs.tailscale.com/${TAILSCALE_CHANNEL}/ubuntu/focal.list | tee /etc/apt/sources.list.d/tailscale.list \ && apt-get update \ && apt-get install -y tailscale=${TAILSCALE_VERSION} \ && apt-get clean \ && rm -rf /var/lib/apt/lists/*