How to Route a Container Through a VPN with Gluetun (Privacy for One App, Not the Whole Server)

Sometimes one app should go out through a commercial VPN — a scraper or changedetection watch (tutorial 135) a site keeps blocking, an RSS fetcher, a download client, anything whose traffic you'd rather not tie to your home IP — while the rest of the server (Pi-hole, backups, Jellyfin) stays on the normal connection. Gluetun is a container that connects to your VPN provider; any other container you attach to it sends all its traffic through that tunnel, with a kill switch so nothing leaks if the VPN drops.

From your provider's account page, generate a WireGuard configuration (Mullvad, Proton, AirVPN, Surfshark, NordVPN and most others offer one). You need the private key, the address, and for some providers a preshared key. Gluetun's wiki lists exact variables per provider.

mkdir -p ~/docker/vpn && cd ~/docker/vpn
nano compose.yaml

services:
gluetun:
image: qmcgaw/gluetun:latest
container_name: gluetun
cap_add:
- NET_ADMIN
devices:
- /dev/net/tun:/dev/net/tun
ports:
- "127.0.0.1:5001:5000" # ports of ATTACHED apps are published here
environment:
VPN_SERVICE_PROVIDER: mullvad
VPN_TYPE: wireguard
WIREGUARD_PRIVATE_KEY: ${WG_PRIVATE_KEY}
WIREGUARD_ADDRESSES: 10.64.0.2/32
SERVER_COUNTRIES: Netherlands
TZ: Europe/London
FIREWALL_OUTBOUND_SUBNETS: 192.168.1.0/24
HEALTH_VPN_DURATION_INITIAL: 30s
restart: unless-stopped

changedetection:
image: ghcr.io/dgtlmoon/changedetection.io:latest
container_name: changedetection-vpn
network_mode: "service:gluetun"
volumes:
- ./cd-data:/datastore
depends_on:
gluetun:
condition: service_healthy
restart: unless-stopped

The attached app has no ports: and no networks: — it shares Gluetun's network entirely. Its web port is published on the Gluetun service instead. FIREWALL_OUTBOUND_SUBNETS lets the attached app still talk to your LAN (for ntfy at home, say); without it, only the tunnel is allowed.

docker compose up -d
docker compose logs gluetun | tail

"Initialization sequence completed" / "healthy" means the tunnel is up.

docker compose exec gluetun wget -qO- https://ipinfo.io
docker compose exec changedetection-vpn wget -qO- https://ipinfo.io

Both should show the VPN's address and country, not yours. Then on the host, curl ifconfig.me still shows your home IP — the rest of the server is unaffected.

Gluetun's firewall allows traffic only through the tunnel. If the VPN drops, attached containers lose the internet rather than leaking; Gluetun reconnects and they resume. docker compose exec gluetun wget -qO- https://ipinfo.io during a reconnect simply fails, which is the behaviour you want.

Any number of services can use network_mode: "service:gluetun". Each one's port is published on Gluetun's ports: list. They see each other on localhost (they share a network namespace), so an app and its own database both attached can use localhost:5432.

• Port forwarding from the provider (VPN_PORT_FORWARDING: on) for apps that need an incoming port — Proton and AirVPN support it.
• HTTP proxy (HTTPPROXY: on, port 8888) so unattached containers can opt in per request — changedetection's proxy setting, say.
• Server switching: SERVER_CITIES, SERVER_HOSTNAMES, or UPDATER_PERIOD: 24h to refresh the provider's server list.
• Health: Gluetun exposes a health endpoint; Uptime Kuma (35) can watch http://127.0.0.1:9999 if you publish it.

Attached container can't start: "network_mode: service:gluetun" error. Gluetun must be in the same compose file (or use container:gluetun), and it must be healthy first — the depends_on condition handles ordering.

UI port doesn't respond. You published it on the app, not on Gluetun. Move it.

Attached app can't reach ntfy/Pi-hole on the LAN. FIREWALL_OUTBOUND_SUBNETS with your LAN range.

DNS inside attached containers fails. Gluetun uses the provider's DNS over the tunnel by default (DOT: on); if the provider blocks it, set DNS_ADDRESS to 1.1.1.1.

Changed provider details, still the old server. Recreate: docker compose up -d --force-recreate gluetun.

One Gluetun container with the provider's WireGuard details, network_mode: "service:gluetun" on the apps that need privacy, their ports published on Gluetun. Those apps leave through the VPN with a kill switch; Pi-hole, backups and everything else carry on exactly as before.