Alpine Linux

Install Docker on an Alpine Linux server in preparation for running Bearicorn.

Requirements

• Alpine Linux 3.20 or later
• SSH access (typically as root on a fresh server)

Installation

Step 1 - Create an admin user

It is recommended to avoid running services as root. Create a non-root user with sudo access:

adduser deployadmin
addgroup deployadmin wheel
install -d -m 755 /etc/sudoers.d
printf '%%wheel ALL=(ALL:ALL) ALL\n' > /etc/sudoers.d/wheel
chmod 440 /etc/sudoers.d/wheel

Log out and back in as deployadmin before continuing.

Step 2 - Install Docker

The steps below follow the Alpine Linux Docker wiki.

apk update && apk upgrade
apk add sudo curl git openssl docker docker-cli-compose
rc-update add docker default
service docker start

Add your user to the Docker group (replace deployadmin with your username if different):

addgroup deployadmin docker

Open a new SSH session for the group change to take effect.

Verify the installation:

docker version
docker compose version

Step 3 - Configure the firewall

Alpine Linux does not include a host firewall. Use a cloud-level firewall (AWS Security Groups or DigitalOcean Cloud Firewall) and allow the following ports:

Port	Purpose
22	SSH
80	HTTP — required for HTTPS certificate requests
443	HTTPS

Next Steps

Continue to choose and deploy your stack.