GCP run docker openvpn error

ERROR: Cannot open TUN/TAP dev /dev/net/tun: Operation not permitted (errno=1)

Solution:
Modify docker-compose.yml, allow container access /dev/neet/tun

version: '2'
services:
openvpn:
cap_add:
- NET_ADMIN
image: kylemanna/openvpn
container_name: openvpn
ports:
- "1194:1194/udp"
restart: always
volumes:
- ./openvpn-data/conf:/etc/openvpn
devices:
- /dev/net/tun:/dev/net/tun # 允许容器访问 TUN 设备