I have a serious problem here. After messing up with my server (I installed ntop and ntopng which had a port error because port 3000 was binded by nghttpx) I uninstalled ntop and ntopng and then at the next reboot I get the error:
winpack.cf systemd[1]: Starting HTTP/2 proxy...
winpack.cf nghttpx[768]: 14/Apr/2016:21:07:16 +0300 PID768 [WARN] shrpx_config.cc:2012 frontend-no-tls: deprecated. Use no-tls keyword in frontend
winpack.cf nghttpx[768]: [FATAL] Too few arguments (shrpx.cc:2060)
winpack.cf nghttpx[768]: 14/Apr/2016:21:07:16 +0300 PID768 [WARN] shrpx_config.cc:2016 backend-no-tls: deprecated. backend connection is not encrypted... backend-tls
winpack.cf nghttpx[768]: Usage: nghttpx [OPTIONS]... [ ]
winpack.cf nghttpx[768]: A reverse proxy for HTTP/2, HTTP/1 and SPDY.
winpack.cf systemd[1]: nghttpx.service: Control process exited, code=exited status=1
winpack.cf systemd[1]: Failed to start HTTP/2 proxy.
winpack.cf systemd[1]: nghttpx.service: Unit entered failed state.
winpack.cf systemd[1]: nghttpx.service: Failed with result 'exit-code'.
By the way, you can do testing at my domain (winpack.cf), but the weird is that Apache correctly serves HTTP/2 without nghttpx!
What's going on here? How can I fix the above error? I can provide any additional log you may need.