DNS Delegation on IPv4


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Nov 2, 2020
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I use my own ns1/ns2 for DNS delegation with ARIN. I edit rDNS per /24, per zone file via cPanel/WHM or SSH console. The zones are created via WHM interface, easily for me.

Now, recently I acquired a legacy block of IPv4 from an ISP. Because it's legacy, they're only able to do a reallocation in ARIN to my account and DNS can only be updated on the full subnet size, let's use /20 for example. I cannot do the usual per /24 DNS delegation in ARIN just because they are legacy IPs.

So my question is, if a client asked for full DNS delegation, like the example below, how would I set this up for them?

Whether it’s a /24 or larger, what would the dns zone file look like?

Below is an example of one created by cPanel and I update for individual IPs per /24, however a full DNS delegation I’m not sure how to do once I update the NS for the /20 with ARIN to point to ns1/ns2.mydomain.com

Example DNS zone for individual IPs on a /24

Filename: 36.222.111.in-addr.arpa.db
In summary, I will have to do full DNS delegation on the whole /20 legacy block to ns1/ns2.mydomain.com and then on my DNS server, will have to server /24 or larger DNS delegation per client as needed. This is where I do not know what the zone file should look like.
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G'day Bashed, Welcome to linux.org

What you have described above is so far above my paygrade, I get dizzy just thinking about it....

However.....I am sure there are others here who will delight in helping you.
Likewise here, Brian :)

@Bashed - take a look at our subforums, and tell me which one this is best suited to, eg Server? If so, which type?

I can move you there for more specialised help.

In General, if you are not answered within a day, you will trail off into obscurity.


Chris Turner

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