OpenVPN server + tap mode = error: one of ifconfig or ifconfig-ipv6 must be specified on Android

havastamas

So i have an OpenVPN server with tap mode, (VPN interface bridged to LAN interface) - i would like to access my local network like if im at home.

On my windows client everything works good, like network discovery, etc.

With my android phone, when i export the android settings, and i would like to connect, i have an error:

19:45:59.398 -- EVENT: ASSIGN_IP

19:45:59.406 -- TUN Error: tun_prop_error: one of ifconfig or ifconfig-ipv6 must be specified

19:45:59.407 -- EVENT: TUN_SETUP_FAILED info='tun_prop_error: one of ifconfig or ifconfig-ipv6 must be specified'

19:45:59.412 -- EVENT: DISCONNECTED

19:45:59.442 -- Client exception in transport_recv: tun_exception: not connected

19:45:59.448 -- EVENT: CORE_THREAD_INACTIVE

19:45:59.449 -- Tunnel bytes per CPU second: 0

19:45:59.451 -- ----- OpenVPN Stop -----

I tried to push config with client specific overrides, but its not working.

push "topology-subnet";ifconfig-push 192.168.1.205 255.255.255.0;

My LAN network is: 192.168.1.0/24,
My router/dhcp server/pfsense local adress is: 192.168.1.1
My LAN dhcp range is: 192.168.1.101-199

Any idea what im doing wrong?

Rico

TAP mode is not supported in either Android or iOS.

-Rico

havastamas

So there is no solution. Should i add another OpenVPN server with tun mode? It can be done without messing something?

Rico

Sure...you can have as many OpenVPN Instances in different modes as you want.
Do you really need to carry layer 2 information via the VPN?
What would be your problem with TUN mode?

-Rico

Rico

TAP benefits:

behaves like a real network adapter (except it is a virtual network adapter)
can transport any network protocols (IPv4, IPv6, Netalk, IPX, etc, etc)
Works in layer 2, meaning Ethernet frames are passed over the VPN tunnel
Can be used in bridges

TAP drawbacks

causes much more broadcast overhead on the VPN tunnel
adds the overhead of Ethernet headers on all packets transported over the VPN tunnel
scales poorly
can not be used with Android or iOS devices

TUN benefits:

A lower traffic overhead, transports only traffic which is destined for the VPN client
Transports only layer 3 IP packets

TUN drawbacks:

Broadcast traffic is not normally transported
Can only transport IPv4 (OpenVPN 2.3 adds IPv6)
Cannot be used in bridges

-Rico

havastamas

Its my home network. Sometimes i would play with my Xbox far away from home - im travelling much.
With tap mode, remote stream/play/power-on works well, and i cant get it to work with tun mode. But i would not run another service just for my phone - but i have no choice..