What needs to be backed up of course depends on the requirements, e.g. some folks need logs for auditing requirements. The ideal tool to take care of it would the Repository Snapshot Manager (Using the Repository Snapshot Manager ‒ Qlik Sense) since it'll take care of all the files / folders that are needed to restore the site. For a schema of a tool which I have used before with success is RepositorySnapshotManager.exe -backup -ver=126.96.36.199 -path="c:\QlikSenseBackups" -u=DOMAIN\QlikSenseServiceAccount -p=DoNotUseThisPasswordChangeToYourOwn -databasePassword=DoNotUseThisPasswordChangeToYourOwn -certificatePassword=password -f
Migrating to a new machine is more complicated than a simple backup and restore the same machine. The complicating factors include but are not limited to: host.cfg has a base64 encoded servername so it will need to be adjusted and server certs are generated to the hostname from the trusted root.
I suspect your partner manager has folks who may have a document ready to go or mostly ready to go to walk through the steps. A colleague in support has a document which he put together but I'd rather not post it out there since it's a quick draft (targeted primarily for our consultants) and not a fully vetted guide. You can create a ticket with support and reference this thread and I'll see if we can provide something.
Odd. I've attached a fully working version of the Repository for 2.2.4 (there were some bugs in the 2.2.4 build in some circumstances). This is a standalone .EXE so it can be moved to where-ever and ran from where-ever