Bug: Iptables error

[lordnegre]

Is this urgent?

No

Host OS

Debian

CPU arch

x86_64

VPN service provider

ProtonVPN

What are you using to run the container

docker run

What is the version of Gluetun

1a25f73

What's the problem 🤔

Any version after 3.41.1 provokes restricted nat on qbittorrent. After checking log output, I've figure out that iptables commands are failing. Maybe, it might be the issue.

Reverting the image from latest to 3.41.1 fixes it.

Share your logs (at least 10 lines)

WARN [iptables] restoring IPv4 iptables failed: exit status 2: Bad argument `[unsupported
Error occurred at line: 28
Try `iptables-restore -h' or 'iptables-restore --help' for more information.: restoring from data:
# Generated by iptables-save v1.8.11 on Fri May 22 09:18:58 2026

Share your configuration

vpn:
    image: qmcgaw/gluetun:v3.41.1 #latest (it works on 3.41.1, not on latest)
    container_name: protonvpn
    cap_add:
      - NET_ADMIN
    devices:
      - /dev/net/tun:/dev/net/tun
    environment:
      - TZ=Europe/Rome
      - VPN_SERVICE_PROVIDER=protonvpn
      - VPN_TYPE=openvpn
      - VPN_PORT_FORWARDING=on
      - PORT_FORWARD_ONLY=on
      - NETWORK=192.168.1.0/24  # So it can be accessed within the local network
      - VPN_PORT_FORWARDING_UP_COMMAND=/bin/sh -c '/usr/bin/wget -O- --retry-connrefused --post-data "json={\"listen_port\":{{PORTS}}}" http://127.0.0.1:8082/api/v2/app/setPreferences 2>&1'
    volumes:
      - /rootfolder:/gluetun
    ports:
      - 8082:8082
    restart: unless-stopped

[github-actions]

@qdm12 is more or less the only maintainer of this project and works on it in his free time.
Please:

• do not ask for updates, be patient
• 👍 the issue to show your support instead of commenting
  @qdm12 usually checks issues at least once a week, if this is a new urgent bug,
  revert to an older tagged container image