Bolt Card Hub - Phoenix Edition

features

• host bolt cards
• web admin
• low resource use

technologies

• Phoenix Server
• SQLite database
• docker deployment

install

• provision an m.1s VPS on lunanode using the Debian 12 64-bit template
  ($3.50 per month, LunaNode accept bitcoin and are lighting enabled for payments)
• log in to the machine using SSH (Linux) or Putty (Windows)
• install docker
• enable managing docker as a non root user
• initialise the system as below
• enter hub.yourdomain.com and set up an A record pointing to the VPS

docker volume create phoenix_data
docker volume create caddy_data
docker volume create caddy_config
docker volume create card_data
git clone https://github.com/boltcard/hub
cd hub
./docker_init.sh

• for a full local build from source and start

docker compose build
docker compose up

• optional stage to remove a Caddy note about buffer sizes and maybe increase performance

sudo nano /etc/sysctl.d/60-custom-network.conf

• add these lines and reboot

net.core.rmem_max=7500000
net.core.wmem_max=7500000

• wait for a few minutes for the TLS certificate to be installed
• access the admin web interface at https://domain-name/admin/ to set a password and login

to keep the service running

docker compose up -d
docker compose logs -f

to get the phoenix server seed words

sudo cat /var/lib/docker/volumes/hub_phoenix_data/_data/seed.dat ; echo

to access the database

sudo apt install sqlite3
sudo sqlite3 /var/lib/docker/volumes/hub_card_data/_data/cards.db

misc SQLite

sqlite> .tables
sqlite> .schema settings
sqlite> select * from settings;
sqlite> update settings set value='' where name='admin_password_hash';
sqlite> .quit

to backup card keys

sqlite> .dump cards

to delete the database

sudo rm /var/lib/docker/volumes/hub_card_data/_data/cards.db

to get a shell on a container

docker container ps
docker exec -it ContainerId sh

after updating - check that docker disk use is reasonable

df -h
docker system df
docker system prune

docker configuration

• docker compose suggests adding export COMPOSE_BAKE=true to your .profile, don't do this (March 2025), it doesn't alway pick up changes
• to persist the docker compose environment across reboots for production use

sudo nano /etc/systemd/system/docker-compose-app.service

[Unit]
Description=Docker Compose Application Service
Requires=docker.service
After=docker.service

[Service]
Type=oneshot
RemainAfterExit=yes
WorkingDirectory=/path/to/your/docker/compose/directory
ExecStart=/usr/bin/docker compose up -d
ExecStop=/usr/bin/docker compose down

[Install]
WantedBy=multi-user.target

sudo systemctl enable docker-compose-app.service
sudo systemctl start docker-compose-app.service