Would Cmd-R and/or Option-Cmd-R work if I prohibit external booting on a T2 Mac?

[Luba]

I’m assuming the external booting prohibition setting is meant for USB-C sticks, so Cmd-R (Recovery) booting would work, correct?

But what if Recovery got corrupted, would Option-Cmd-R be able to boot a T2 Mac if I set the security to prohibit external booting?

 

[barbu]

yes I imagine it would prompt for your admin password when you attempted to do so. might be worth a test ;-)
and as you say, this doesn't apply to internal partitions like Recovery.

 

[Luba]

yes I imagine it would prompt for your admin password when you attempted to do so. might be worth a test ;-)
and as you say, this doesn't apply to internal partitions like Recovery.

Option-Cmd-R does work!

Also, it seems like you can boot from an external if you go through Recovery and then select a Startup Disk when you want to exit out of Recovery and Restart. I did this by going through Internet Recovery (Option-Cmd-R), but I thought Internet Recovery only allowed me to reinstall macOS. Internet Recovery also contains all the other Utilities like Disk Utility, Online Help, Startup Security Utility, etc? Or was I really accessing the Utilities in Recovery (not Internet Recovery) since my Recovery partition is not corrupted.