Issue DNS records not working after creating subdomains

[JeffreySB]

Since a few months we're having trouble creating subdomains in our plesk environment.
We have over 100 subdomains and domains, but since a few months, when we create a subdomain and the required A record in the main domain, we keep getting "DNS_PROBE_FINISHED_NXDOMAIN" in Chrome, stating that the A-record can't be found, while it is obviously there.
We've waited to propagatie across the DNS servers worldwide, but unfortunately no luck.

When we create a subdomain, we'll use the default DNS settings for that subdomain: ns1.subdomain.example.com and ns2.subdomain.example.com.
In the main domain we'll create an A record with subdomain.example.com and the IP Address of our server (as we've always done for the past subdomains).

I've searched on this forum and other, but haven't found a solution yet.
We've updated Plesk last month, but that wouldn't fix the issue either.
We haven't updated all packages yet, but could that really be the problem?

Anyone know how to fix this, or check where this is going wrong somewhere in logs?

Here are the server details:
CentOS Linux 7.6.1810 (Core)

Plesk Obsidian
Version 18.0.36, last updated on June 24, 2021 05:20 PM

 

[IgorG]

Have you tried to troubleshoot it with the help of this KB article, for example?

Unable to open subdomain, alias or webmail hosted in Plesk: This site can’t be reached DNS_PROBE_FINISHED_NXDOMAIN

Applicable to: Plesk for Linux Plesk for Windows Symptoms WWW alias, website's subdomain or webmail URL that are hosted in Plesk cannot be opened with the following error: CONFIG_TEXT: This si...

support.plesk.com

 

[JeffreySB]

Yes, we tried adding the A-record to the main domain name, but unfortunately that doesn't work.
Somehow it seems like the A-record doesn't get "through" or "published" in Plesk, because on MXtoolbox he still doesn't find any A-records.

 

[mow]

have you tried dig NS subdomain.example.com to check whether the correct NS is asked? Do you get an "answer section" or "authority section"?
(or use set q=ns with nslookup)

 

[JeffreySB]

have you tried dig NS subdomain.example.com to check whether the correct NS is asked? Do you get an "answer section" or "authority section"?
(or use set q=ns with nslookup)

When I'm tring to lookup NS on subdomain.example.com, I'm getting "no records found". I've got that same error when looking up existing subdomains that are working.

When creating the subdomain in Plesk, it automatically makes 2 NS records: ns1.subdomain.example.com and ns2.subdomain.example.com
Normally this would work and no warning appears in Plesk.
But now with every newly created subdomain it states:

The website's domain name does not resolve or resolves to a different IP address.
To put your website online, update DNS settings on the side of your domain registrar or external DNS provider.

Your website will be up and running once DNS changes come into effect. It may take up to 24 hours.

 

[mow]

And when you dig NS example.com, what is listed as the nameserver(s)?

 

[JeffreySB]

And when you dig NS example.com, what is listed as the nameserver(s)?

ns1.example.com.
ns2.example.com.

 

[belen_g]

Hello @JeffreySB, by any chache did you manage to solve this? it´s the same problem a have.
Thanks

 

[JeffreySB]

Hello @JeffreySB, by any chache did you manage to solve this? it´s the same problem a have.
Thanks

Yes, we've managed to solve this, but it was more of sum of things that weren't working properly.
Our firewall was blocking the DNS port, so other DNS servers couldn't read the DNS changes. Also we've done some changes in the DNS config to let the AXFR records work.