Here is a list of steps for upgrading my Cacti virtual appliance in place retaining all data. This will only work on the Centos7_Cacti-v1.1.6 or greater. This assumes you are still using the original Cacti user, passwords, and paths.
If there are any questions, please use GitHub Issues, and I can assist and update as needed.
[Update 12/4/2018]
It turns out there has been some development in Smokeping after almost 4 years of quiet! New v2.7.2 is available, so I created a new Smokeping update routine and added it to the script. This will check if you have Smokeping installed, and offer to upgrade if you wish. This can be run via the same routine as the Cacti upgrade from Github below.
[UPDATE 11-28-2018]
I have a first working version of an automated update routine for the cacti-template you can get here. You can get the instructions on how to run it here…