Okay I got it. In 4.8, non-Cascading shadow Maps is broken. Usually with 4.7 you can set Dynamic Shadow Distance to 0 and nothing is wrong with the shadow. However, in 4.8 this will result in many shadow disappearing.
For anyone having the same problem, you probably have to go in and readjusting all those Dynamic shadow distance settings and etc to use the cascade map for now.