Domain Controler order network

Hello everybody, I need help

I have only one domain with two domain controllers, I wonder how is the order in DNS servers that are domain controllers, both in primary and in secondary:

Today I left it this way:

DC Principal

IP: 192.168.0.1
Mask: 255.255.255.0
Gateway: 192.168.0.4

Primary DNS: 192.168.0.2
Secondary DNS: 192.168.0.1

________________________________

Secondary DC

IP: 192.168.0.2
Mask: 255.255.255.0
Gateway: 192.168.0.4

Primary DNS: 192.168.0.1
Secondary DNS: 192.168.0.2

I'm following the practices of MBSA, however there is a discução around it saying it should be another setting ie, each DC pointing to your own IP Primary DNS field.

I understand that if the DC Principal fall, he will point to the secondary and vice versa,

However I wonder if my thinking is correct?

thank you

MCP