Let's say I have two ISPConfig servers and I've registered a domain, say, domain.com, that I want to host on one of the servers. Usually I would just make a primary (master) dns zone on one of the servers, and on the second server I would just make a slave (secondary) zone where I would just state the IP of the first name server holding the DNS master zone. BUT. Will it be OK to make TWO master zones, that is, to make a master zone on each server? Will it be against the rules or not?