Under Advanced -> DHCP Server there appears to be a way to set a Primary and Secondary DNS entry that the clients would receive. However, I can not find a way to add the data. 

To be clear, I'm not referring to the upstream ISP DNS setting.

If this isn't feasible/doable, then how do I disable the DHCP server completely?

Many thanks!

I do wish the Deco had a DNS server fuction, then it really would be a complete solution.  I run a home lab with my own custom domain name and do not want to rely on an external internet DNS server. I'm comfortable managing dnsmasq, but need to point the Deco to it.

Many thanks,