managedsoftwareupdate has several methods you can use to identify your Macs to your Munki server. While the hierarchy is documented on the Munki wiki, the ComputerName field (accessible in System Preferences –> Sharing), is not one of them. Since our inventory system is tied to the computer name, we wanted Munki to use that as the identifier for manifests, too.
I wrote a small LaunchDaemon and script to write the ComputerName field to Munki’s ClientIdentifier field (which overrides the hierarchy mentioned above) each time it’s changed. This allows IT to rename Macs and manifests as needed, but also audit unauthorized computer name changes through MunkiReport.
The code is available on my GitHub repository.