Gluetun X Cyberghost

[Serval-S]

Hello, I try to use Docker gluetun (on synology nas) with cyberghost and I am on the subject thince many hours with GPt and I can't find the solution.
Can someone please help me and fix my issue ?

there's the logs :

2026-04-10T16:30:59Z INFO [routing] default route found: interface eth0, gateway 172.17.0.1, assigned IP 172.17.0.4 and family v4
2026-04-10T16:30:59Z INFO [routing] local ethernet link found: eth0
2026-04-10T16:30:59Z INFO [routing] local ipnet found: 172.17.0.0/16
2026-04-10T16:30:59Z INFO [firewall] enabling...
2026-04-10T16:30:59Z INFO [firewall] enabled successfully
2026-04-10T16:30:59Z WARN flushing conntrack failed: querying netlink request: netfilter query: netlink receive: invalid argument

2026-04-10T16:31:01Z ERROR VPN settings: OpenVPN settings: client certificate: missing value
2026-04-10T16:31:01Z INFO Shutdown successful

Here my compose :

sudo docker run -d
--name gluetun
--restart unless-stopped
--cap-add=NET_ADMIN
--device /dev/net/tun
-e VPN_SERVICE_PROVIDER=cyberghost
-e VPN_TYPE=openvpn
-e SERVER_COUNTRIES=Netherlands
-e OPENVPN_CUSTOM_CONFIG=/gluetun/config/config.ovpn
-e OPENVPN_USER=XXX
-e OPENVPN_PASSWORD=XXX
-v /volume1/docker/gluetun:/gluetun
qmcgaw/gluetun

Here my ovpn :

client
remote 181.214.206.32
remote 181.214.206.47
remote 191.96.168.18
remote 191.96.168.32
remote 191.96.168.156
remote 195.78.54.18
remote 195.78.54.25
remote 195.78.54.54
remote 195.78.54.127

dev tun
proto udp
auth-user-pass

resolv-retry infinite
redirect-gateway def1
persist-key
persist-tun
nobind

data-ciphers AES-256-GCM:AES-128-GCM:AES-256-CBC
data-ciphers-fallback AES-256-CBC

auth SHA256
ping 5
explicit-exit-notify 2
script-security 2
remote-cert-tls server
route-delay 5
verb 4

ca /gluetun/config/ca.crt

cert /gluetun/config/client.crt

key /gluetun/config/client.key