Just trying to Understand-
You have ITSM too or just having a Custom App running on remedy ARS 7.5?
Will a database backup in 7.5 and restore to 7.6.04 affect anything during such an upgrade, or will I have to upgrade the database through the installer, and a restore could break functionality?- Can you elaborate more on this?
For Exact steps on upgrade from 7.5 to 7.6 04- You may need to look for BMC docs 7.6.04 for more details.
One important thing in 7.6.04 is Overlay Creation which helps preserve customization during Overlay.
from 7.6.04 to 8.1 below link will be Helpful.
Also BMC has an AMIGO program which helps customer in Upgrade.
run the BPCU to create overlay of your all customization,your customization will be preserve.
You are planning to upgrade NON-Overlay environment So you need to follow different process as described here:
1. Install fresh 7.5 remedy environment matching your production 7.5 server
2. Take a DB backup from 7.5 Prod server (Please note down date and time) and restore it newly create 7.5 server.
3. If you have any customization on system forms then take a backup of those forms(def files) becuase system forms are overwritten during upgrade. Below is list of system forms:
4. Upgrade AR Server only to 7.6.04 [Do not select any other AR Server components]
5. Run BPCU: to find out your customizations and convert them to overlays and custom objects:
6. Import system form def files taken in point 3.
7. Upgrade other AR Server components
8. Upgrade Atrium and Other applications.
9. Migrate Delta data created in the Prod server. [data created after db backup date noted in point 2]
10. Test and Promote to production.