ics-openvpn VS ovpn-dco

When I am trying to build https://github.com/schwabe/ics-openvpn > main. I am constantly get the following error:

I've been working for a few days to build a good working VPN app (Non-commercial) but I'm finding so many different implementations of https://github.com/schwabe/ics-openvpn that I don't know exactly where to start.

OpenVPN for Android (version 0.7.46): OpenVPN without root

You could ask upstream: https://github.com/schwabe/ics-openvpn (also, is that the app you're using?)

Just the android phone with Openvpn for Android (https://github.com/schwabe/ics-openvpn) thinks that it's too good for a new dns lookup, takes the ip it has cached from the previous connection and therefore can't connect. It retries until i manually disconnect and reconnect it. Only then a new dns lookup happens and it gets the current ip to then connect without a problem.

For the Android app it lists: https://github.com/schwabe/ics-openvpn

I know that Apple limits what you're permitted to install on their phones, but perhaps there's another openvpn version that has this feature that you're permitted to use. In case it can help, the version I'm using seems to be from https://github.com/schwabe/ics-openvpn/ . Perhaps someone has done something similar for Apple phones.

I've been looking into doing something similar and stumbled upon a method that uses personalDNSfilter with OpenVPN for personalDNSfilter, which is a special version of the OpenVPN for Android app.

In addition we back several other open source projects, such as the OpenVPN GUI, OpenVPN for Android and OpenVPN 3 Linux ... these all provide various user interfaces on top of the OpenVPN Core component.

OpenVPN for Android (version 0.7.37): OpenVPN without root

We also back several OpenVPN related drivers, such as tap-windows6 driver, ovpn-dco-win driver, ovpn-dco linux kernel module. The tap-windows6 driver is the old Windows driver, which gives a pretty basic tun/tap interface. The DCO drivers are the next generation drivers, where more of the cryptographic operations are moved into the OS kernel instead of happening inside the OpenVPN Core components; which has the potential to improve the tunnel performance.

With Linux, there's lots of stuff going on in the OpenVPN community, in particular with a kernel module to accelerate the performance. The OpenVPN 3 Linux client already supports it and the coming OpenVPN 2.6 release (currently in development) will add support for both server and client mode with data channel offload (aka DCO).

Here is link number 1 - Previous text "DCO"

All that said, with the work being done in OpenVPN with the Data Channel Offload (DCO), it would probably be easier to get hardware support. The DCO implementations (ovpn-dco, ovpn-dco-win) offloads the data channel crypto operations to the virtual network driver, so the encryption/decryption/packet authentication happens entirely in the kernel space - which results in a noticeable performance boost. The tasks these DCO drivers does should be possible to more easily implement inside some dedicated hardware. But it won't be cheap.

There are work in progress on a OpenVPN kernel module, which will improve OpenVPN performance considerably: https://gitlab.com/openvpn/ovpn-dco