Many use one big-honking Include file with a set of functions used all over the site... at the top of this file, set a variable to indicate when maintenance is being performed or the site is otherwise unavailable, then test for the value before doing any other thing... if "down", server.transfer or response.redirect to your special "site unavailable" page.
Dim doMaintenance, RightNow, MaintenanceStart, MaintenanceEnd doMaintenance = False MaintenanceStart = CDate("6/18/2015 3:00pm") MaintenanceEnd = CDate("6/18/2015 5:00pm") RightNow = Now() If RightNow > MaintenanceStart and RightNow < MaintenanceEnd Then doMaintenance = True If doMaintenance Then Server.Transfer "otherpage.asp"
Hope this helps!