VPN server on RaspPi2 problems

What else is the RaspberryPi doing, and is it using a memory card or USB storage? The latter will be using the single USB bus that the ethernet is on.

That router is pretty slow, my ASUS RT-AC68U is a good bit faster than a

3B. When acting as a VPN gateway a fibre connection can exceed the Pi's 100Mb Ethernet throughput, as the amount of traffic is more than doubled.

Possibly, but you can't solve the hardware limitations. If VPN performance is critical, invest in a better router or something with gigabyte ethernet (the 3B+ may or may not be any better, depending on what the issue is).

---druck

I was able to change niceness of openvpn by setting nice -20 into openvpn.conf. That made repsone time much faster. In addition to that I found out that a virtual machine I am running at wotrk place was configured to connect to my TAP device port and tried to pull a Windows update through vpn connection. (What can go wrong will go wrong)

Now openvpn runs perfectly on Rasp PI.

Regards Andreas

Well done!

--
"In our post-modern world, climate science is not powerful because it is  
true: it is true because it is powerful." 

Lucas Bergkamp

Doing things TAP (bridging) is an overhead, for OpenVPN choosing TUN (routing) is apparently faster - so I invested a bit of time and implemented the latter on a Pi2/Jessie down to the point of even relaying broadcasts packets to the local lan, playing nice with SMB/samba and compatible firewall rules all over the shop.

Amazed how fast it is - I'm not into VPN as a proxy geo thing, just need access to my own network when I'm somewhere else, even over an iPhone - which for kicks maintains a perfect Windows RDP session on 4G while I'm travelling into London on an overground section of the tube.

--
Adrian C