Rounding time to nearest half hour, military format, 10:46 should round to 11:00 etc

I have been browsing through several forums and threads and keep getting formulas that either take the floor or ceiling which is not what I want. I have currently:

=floor(d2, "0:30")

Unfortunately this rounds something like 10:46 to 10:30, which I need to round to 11:00. Any help would be great! Thanks!!

Yes!!! That works! Thanks so much!