@dillon Thank you for your reply. Currently I have 4 layers, two inner layers are power plane and ground plane, respectively, and the top and bottom layers are signal layers. I only want the auto router to route on the top and bottom layers. But there is no option to designate it. I tried selecting the "TOP Only", but the inner layers were still routed.
Do you have any ideas to solve this problem?
Our website uses essential cookies to help us ensure that it is working as expected, and uses optional analytics cookies to offer you a better browsing experience. To find out more, read our Cookie Notice
Brand new interactions and interfaces. 
Easy to use and quick to get started. 