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{Qustion} Reverse DNS setup at ARIN

Thanks for reading this article, first.

I read this article ( to better understand reverse DNS.

We got a IP block /24 through ARIN. For example, we got 198.x.x.x/24 like below.      


When I select a delegation "" I can setup hostname of name servers like below.


This is my quesiton.

1. We have two Public DNS servers. one of DNS server's public IP will be same range 198.x.x.x/24 and other will be different IP address. As I understand it doesn't matter whether I use any hostname of DNS. i.e, etc because it just uses for DNS lookup. Am I correct?

2. Once I setup, ns? as Reverse DNS at ARIN's website, every traffic belonging to our public IP range (198.x.x.x/24) will be resolved through our public DNS servers. Am I correct?

3. I need to better understand DS. Currently DS (Delegation Signer) record is /24 ( and I can assign hostname of name servers as multiple.  is it possible to assign /32 host with directly dns name?  i.e with so I don't use any public DNS server. I guess not. ^_^


4. One of ISP asked me to choose one of options for Reverse DNS like below. In my case, I believe I need to select "No" since we are authorative for this IP blocks. Am I correct?  I guess when I need to lease IP blocks through ISP, I check "Yes" to get their Reverse DNS service.

    Do you need xxx (ISP name) to resolve reverse DNS?
     [   ] No
     [   ] Yes (Engineer will work with you during test and turn-up) 
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