Now I want to introduce the use of ‘Configure Physical Nets‘, as follows:
If you has finished the PCB layout, as follows:
Then you want to get rid of these white wires, so the two boards would be separated completely. And you change the nets of the one board, as follows:
The earlier routes collide with the current routes, then you can use ‘Configure Physical Nets‘ to eliminate this problem, as follows:
Altium Designer 15 --- Nets Update
原文：http://www.cnblogs.com/god-of-death/p/6114983.html