Support DD-WRT & OpenVPN

port xxx
proto tcp
dev tun0
ca /tmp/openvpn/ca.crt
cert /tmp/openvpn/cert.pem
key /tmp/openvpn/key.pem 
dh /tmp/openvpn/dh.pem 
server 10.8.0.0 255.255.255.0
push "dhcp-options DNS 8.8.8.8"
push "redirect-gateway def1"
keepalive 10 120
comp-lzo
persist-key
persist-tun
verb 3

root@Privat:~# openvpn /tmp/openvpn/openvpn.conf
Sun Dec 18 17:56:22 2016 OpenVPN 2.4_rc1 arm-unknown-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [MH/PKTINFO] [AEAD]
Sun Dec 18 17:56:22 2016 library versions: OpenSSL 1.0.2j  26 Sep 2016, LZO 2.09
Sun Dec 18 17:56:22 2016 Diffie-Hellman initialized with 2016 bit key
Sun Dec 18 17:56:22 2016 TUN/TAP device tun0 opened
Sun Dec 18 17:56:22 2016 TUN/TAP TX queue length set to 100
Sun Dec 18 17:56:22 2016 do_ifconfig, tt->did_ifconfig_ipv6_setup=0
Sun Dec 18 17:56:22 2016 /sbin/ifconfig tun0 10.8.0.1 pointopoint 10.8.0.2 mtu 1500
Sun Dec 18 17:56:22 2016 /sbin/route add -net 10.8.0.0 netmask 255.255.255.0 gw 10.8.0.2
Sun Dec 18 17:56:22 2016 Could not determine IPv4/IPv6 protocol. Using AF_INET6
Sun Dec 18 17:56:22 2016 Cannot create TCP socket: Address family not supported by protocol (errno=97)
Sun Dec 18 17:56:22 2016 Exiting due to fatal error
Sun Dec 18 17:56:22 2016 /sbin/route del -net 10.8.0.0 netmask 255.255.255.0
Sun Dec 18 17:56:22 2016 Closing TUN/TAP interface
Sun Dec 18 17:56:22 2016 /sbin/ifconfig tun0 0.0.0.0