On T2 Macs we have to allow booting from external media in some cases. Other options are to use internet recovery or MDS.
The new M1 Macs allow external booting by default, just like the old Mac days. To make things consistent across old Mac, T2 Mac and M1 Mac... can we allow external booting on T2 Macs using Jamf?
I'm also curious about this. We have a store of MacBook Pros which are on Catalina, which will set up with DEP. We'd like to upgrade them to Big Sur without having to log in, create an admin account, upgrade, and then wipe. Is there a method of allowing external boot without the whole process?
Well, if we're running the macOS installer from another Mac and simply installing down to the drive as normal otherwise. it's not a copy so much as installing the OS to an external drive. That is still supported, afaik?
A really big critique of mine with Apple about this...
Dissallow external disk booting (Even to disks/volumes that have been created with createinstallmedia) (aka macOS recovery built by an a Install macOS *.app)...
They should have kept/allowed external booting to signed macOS installers (those created by createinstallmedia) then prevent internal disk erasure without a password.