What will happen if we make local DNS root DNS ?

DNS is the backbone of internet. We will simply find lots of blog about DNS mentioning about it being a phonebook also helps to find out the authoritative IP for the querying domain name. DNS itself is quite a vast topic and there are different entities associated with it. There are things like recursive query , iterative query, forward zone, reverse zone, forwarding, conditional forwarding and so on.

Let me know briefly describe about adding a root zone that I recently came across and some interesting changes that I came across after adding it. Root hints are a list of the DNS servers on the Internet that your DNS servers can use to resolve queries for names that it does not know. When a DNS server cannot resolve a name query by using its local data, it uses its root hints to send the query to a DNS serve. We can also find the root DNS screenshot below.

Root DNS are used in conjunction with recursion and if recursion is not used then it will only be able to answer query from its own local database. We will make our local DNS server as root dns and see what will happen.

I have added a Zone name with a dot (.)which basically means a root DNS server. Now the local DNS will not be able to forward the query to 13 root DNS server for the query that it doesn't have database of for example google.com as all of the 13 root DNS server has been removed. We will need to remove root from the local DNS again to do the recursive query to the 13 available root DNS.

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