Hello @Jasim KP !
No it is not mandatory
When you have no forwarder , the DNS resolves via the Root Hints
In general it is a good practice for these reasons :
When you configure DNS forwarders, you specify external DNS servers (typically provided by your ISP or a public DNS provider) to which DNS queries that cannot be resolved by your local DNS server will be forwarded. This allows your DNS server to resolve external domain names efficiently without relying solely on root hints or iterative queries.
Here are a few reasons why configuring DNS forwarders is recommended:
1. Improved DNS resolution performance: DNS forwarders can help reduce the response time for external DNS queries. When a DNS query is forwarded to a DNS forwarder, the forwarder can quickly resolve the query and provide the response to your DNS server, which improves overall DNS resolution performance.
2. Reduced external network traffic: With DNS forwarders, your DNS server can offload the responsibility of resolving external domain names to the forwarder. This reduces the amount of external network traffic generated by iterative queries and can help improve the overall network performance.
3. Redundancy and reliability: By configuring multiple DNS forwarders, you can create redundancy in DNS resolution. If one forwarder becomes unreachable or experiences issues, the DNS server can automatically switch to using the alternate forwarders, ensuring continued DNS resolution.
So in a few words it is good to have a Forwarder , e.x your ISPs DNS , for improved speed and not relying on the Root Hints!
I hope this helps!
Kindly mark the answer as Accepted and Upvote in case it helped!
Regards