Part of this setup Nginx, MySql, PHP and WordPress. This part is for configuring Varnish 4.0 on Ubuntu 14.04

On varnish.chris.example.com

Install Varnish 4.0

1. Add Varnish’s GPG key
   curl https://repo.varnish-cache.org/ubuntu/GPG-key.txt | sudo apt-key add -
2. Add the source location
   echo "deb https://repo.varnish-cache.org/ubuntu/ trusty varnish-4.0" | sudo tee /etc/apt/sources.list.d/varnish-cache.list
3. Update local cache
   sudo apt-get update
4. Perform a version check to make sure that Varnish 4.0 is listed:
   sudo apt-get install -s varnish
5. Install
   sudo apt-get install varnish

Configure Varnish

1. Edit the main config file for Varnish
   sudo vi /etc/default/varnish
2. Change the 6081 to 80 in this block.
   Before

   DAEMON_OPTS="-a :6081 \
                -T localhost:6082 \
                -f /etc/varnish/default.vcl \
                -S /etc/varnish/secret \
                -s malloc,256m"
   

   After

   DAEMON_OPTS="-a :80 \
                -T localhost:6082 \
                -f /etc/varnish/default.vcl \
                -S /etc/varnish/secret \
                -s malloc,256m"
   

3. Restart Varnish
   sudo service varnish restart