lastest nginx for ubuntu 14.04 compile with older version openssl then not support ALPN.
Unfortunately, chrome is not support http2+NPN, only support http2+ALPN.
require recompile nginx with new version openssl
Original : https://alex.bouma.me/recompile-nginx-with-openssl-1-0-2-for-http-2-via-alpn-ubuntu-14-04/
# Install package building tools
sudo apt-get install -y dpkg-dev
# (optional) cleanup previous work directory
#sudo rm -R /opt/nginx
# Create a work directory
sudo mkdir /opt/nginx
# Switch to our work directory
cd /opt/nginx
# Get NGINX source files
sudo apt-get source nginx
# Install NIGNX build dependencies
sudo apt-get -y build-dep nginx
# Switch to the source files directory
# You might need to change the version number in your case
cd nginx-1.*
# Build the .deb package files
sudo dpkg-buildpackage -b
# Move back to out work directory where the .deb files are placed
cd /opt/nginx
# Stop NGINX
sudo service nginx stop
# Install the newly build .deb file
sudo dpkg --install nginx_1.*~trusty_amd64.deb
# Start NGINX
sudo service nginx start