How to delegate a sub-domain to other DNS servers

To do this, you need to add NS-records for the sub-domain name pointing to the host names of the DNS servers hosting the sub-domain -  in the parent zone.

In the "DNS records" window right-click the parent zone in the left list and select "New NS-record":

In the "New NS-record" dialog, enter the sub-domain name and the host name of one of the DNS servers hosting the sub-domain:

Repeat the previous steps, so that you have an NS-record for each DNS server hosting the sub-domain:

Note that it is important that matching A-records exist for DNS server host names listed in these NS-records.
For the example above, A-records must exist for "" and "" - in the "" zone on whatever DNS server is hosting "".

If the DNS server host names are themselves sub-names of the domain name being delegated, it is necessary to include a copy of these A-records in the parent zone. These are called "glue records".
Otherwise other DNS servers will have no way to find the sub-domain's DNS servers, and therefore no way to resolve records in the sub-domain.
In the screen shot below, the highlighted A-records are such "glue records":

Related KB articles:

18 May 2016 22:29 UTC
Picture #3 seems to be wrong. There should be an A record for, and ns2, just like the text under the picture explains
JH Software
2 Sep 2016 16:43 UTC
JH Software
No - it is not possible to have records for another domain in the zone. Those records belong in the "" zone - wherever that is hosted.
That is also what the text under the picture states - if you read the paragraph to the end.
28 Dec 2016 12:22 UTC
Lallabi Innovations
Is it beneficiary to host each sub domain separately?
Actually I have a domain like and having many sub domains like, I hosted all the sub domains with primary domain and having same name servers for all the sub domains and to main domain. Now someone suggested me to keep seperate name servers for each sub domain. Is it helpful or not? and How? Can you please answer me.
JH Software
9 Jan 2017 11:56 UTC
JH Software
If you have no specific reason to do so - then no.
The typical reason for doing so is that you want to delegate responsibility for the sub-zone to someone else.
You might also consider it if the sub-zones are very large - and therefore easier to manage as separate zones.
6 Dec 2017 09:02 UTC
Kashif Faraz
it is possible that Top Level Domain and Sub Domain has different NS(Name server)?
JH Software
6 Dec 2017 09:27 UTC
JH Software
Yes, this is possible. And very common.
12 Jul 2021 03:38 UTC
I just wanted to say it's 2021 and this article is STILL helpful
7 Oct 2021 08:38 UTC
How can a delegation have a different domain name?
For example at this address ( look at fig. 1-26.
There is no possibility to choose another domain name.
JH Software
7 Oct 2021 10:02 UTC
JH Software
You can only delegate sub-names.
For example if you own and host DNS for "", you can delegate DNS for anything "under" - like "".
Please note that the link you mention is about Microsoft's DNS server software - not Simple DNS Plus, but the same still applies.
19 Nov 2022 04:13 UTC
Ankit Sharma
Creating NS record under same domain may cause circular reference.
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