To run this playbook, you will need to run lucascbeyeler.baseline too.
We do not cover any kind of server preparation, like upgrade the system or change the hostname (even put the hostname in /etc/hosts is made by commons).
Best practice in general is to install Zimbra on a virtual machine and use LVM or another technique that supports snapshots.
This way you can create snapshots and in case anything goes wrong you just roll back to your snapshot.
You can upgrade after you installed your old Zimbra version on your new OS but you CAN NOT upgrade your OS and Zimbra at the same time.
Be sure to read the release note information before upgrading.
Bug 105056 noted a problem that can occur during a rolling upgrade if two factor authentication (2FA) is enabled before all mailbox servers have been upgraded to 8.7.
In my case there wasn't even an installer for Ubuntu 14.04 so basically I could only roll back to my Snapshot and start again. Again: I wanted to upgrade from Ubuntu 12.04 to 14.04 and Zimbra 8.0.5 to 8.6.
In my case, there was no installer for Zimbra 8.0.5 on Ubuntu 14.04, but there was a 8.6 installer for Ubuntu 12.04.
screen wget https://files.zimbra.com/downloads/8.6.0_GA/zcs-8.6.0_GA_1153. UBUNTU12_64.20141215195814tar xzf zcs-8.6.0_GA_1153. This might take a while but makes sure your database is intact.