I had all sorts of VPN problems over the years with various Linux desktops OS. What I do instead is that I have a proxy server with just an OpenSSH daemon on port 443 -- if there's web traffic, add sslh to taste -- and then use the SOCKS v5 proxy built into OpenSSH client and then http://darkk.net.ru/redsocks/ I might be the weird case here but I found this infinitely easier to set up than any VPN.