This is a command line related question, not X. For years under sysvinit, in /etc/inittab, this line: kb::kbrequest:$( [ "`id -u`" -eq 0 ] && /bin/openvt -su || sudo /bin/openvt -su) allowed me to open another VT by keying Control-UpArrow.
I've had no luck generating that same functionality under systemd. If anyone else has managed to do this I'd sure appreciate a primer. Actually if there is another way to achieve the same results I'll gladly put kbrequest aside. Thanks, Mike