Is anyone here booting the OS from a T3/T5 external SSD?

[stoker1]

Stoker 1.

You need to set up for booting the external through Disk Utility.

Open DU, show "All Devices"under 'View', select the external destination drive, hit erase, if running APFS, choose APFS format and GUID, erase, and nthen runner SD and it will be bootable. This is as Dave Ninian of ShirtPocket replied when I could not boot from either of my two external SSDs.

Thanks very much "nambuccaheadsau",, somehow, I managed to do what you mention , and worked out fine, so now finally have put Mojave on this SSD, which I can boot from. Think I will try , while I am at it, to Restore a Time Machine backup to this SSD when I pick a certain date that had Mojave backup. I really thought that OS Mojave boot up on this SSD would load up faster. I guess will try and plug directly into my Mac