Pitfall of Ubuntu 14.04 to 16.04 Upgrade

Here are some notes that really can get you in trouble with the Ubuntu 14.04 to 16.04 upgrade:

In Ubuntu 16.04, important changes since the preceding LTS release include a transition to the systemd init system in place of Upstart, an emphasis on Python 3 support, and PHP 7 in place of PHP 5.

01.  In a VMware 6.0 environment, using the VMXNET3 ethernet adapter; the interface name will change.  To fix this, go find the new interface name with

lshw -C Network

then fix the /etc/network/interfaces with the new interface name then

ifup <interface_name>

02. Django will definitely break.  To satisfy the dependencies, locate the requirements.txt then

sudo apt-get install python-setuptools
sudo easy_install --upgrade django

pip install --upgrade pip
pip install -r <path/to/requirements.txt>

03. Nginx will also break with the new /etc/nginx/nginx.conf so you might have to use the old nginx.conf.dpkg-old backup 

04.  For Wordpress using NGINX, here is an article that covers all the necessary steps: https://thecustomizewindows.com/2016/09/upgrade-ubuntu-server-14-04-16-04-live-wordpress/