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Author Topic: dns updater  (Read 353 times)


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dns updater
« on: October 03, 2022, 05:17:00 PM »

Hi, I am new here.  I came here looking for Free DNS service provider and that provides PTR reverse DNS record.   

My ISP gives me dynamic public IP so I utilize no-IP or Duckdns DNS service in order to set an A record and I pass that record to my webhost DNS and create CNAME, MX entries from it.  It is well and good because it does the job.  However, my webhost does not provide creation of PTR record.  I needed the PTR record for setting up Postfix.

My ISP also does not give me PTR record.  So I came across google search about free DNS service where I can create PTR record.  I have not tried it yet.  So, if that is true that I can create all DNS  entries related to mail server, then it is well and good.

So the next thing that I would like to resolve is have to create a DNS "A" record from a dynamic IP address without using the service like those from no-IP or Duckdns.

I was thinking if could create URL script that can update a DNS entry like this one from Duckdns like below:

echo url="" | curl -k -o ~/duckdns/duck.log -K -

The above URL, updates only the DNS "A" record.  I was wondering if can create URL for update each type of DNS entry that is most likely to change often especially for dynamic IP. free dns service is already an awesome service and if this is coupled with DNS entry updating URL then it will be more helpful especially to the dynamic IP users.

I hope could further extend their awesome service.

Thanks!  :)



  • Hero Member
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Re: dns updater
« Reply #1 on: October 04, 2022, 10:26:17 AM »

Your problem will be securing delegation.  No ISP is going to delegate a single IP address for resolution purposes.

You better hope that the ISP provides a reverse name that resolves.  Otherwise, you’re SOL.


  • Jr. Member
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  • Posts: 71
Re: dns updater
« Reply #2 on: October 04, 2022, 01:16:04 PM »

There is one other possibility.  If you use's tunnel service in addition to their DNS, they will delegate the reverse domain of your tunnel allocations to your DNS account.  There, you can setup appropriate PTR records.  Of course, this means using IPv6 instead of IPv4.