DNS Config in DC

This time I dont have any problems, but coming here slooking for an advice :)

I've 2 DC, both of them DNS servers also, with AD zones integrated. I´ve read that I should point the preferred dns server in each DC to itself, and the alternate to the other DC. But I think this causes the "preparing network connections" take too long, and there are some warnings in the log about DNS not resolving (which I think is due to the dns service still not started).
What is the "ideal" network config for DC being DNS servers also?