What do you mean by will database be touched?
This is a major upgrade and requires maintenance window, especially since CUCM 8.6 requires Red Hat Enterprise upgrade with few reboots. Check out release notes and upgrade guide for more details.
Sorry guys for mis questioning, what I meant was the configuration database (current configuration, users, phones, gateway ..etc.).
The upgrade, as far as I could tell, didn't change any existing settings. It adds lots of new possible settings. If you use external URLs for the Services, Messages & Directories buttons, then you'll need to check out the new HTTPS versions of the URLs, to make sure the installer guessed right. (On my system, it didn't :-/ )
On that aspect, no, it doesn't.
That's the whole purpose of having the active and inactive partitions model.
We get the data from active, and then use it for the upgrade process doing the changes in the inactive so that you just need to switch partitions.
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