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Resolved Plesk DNS Servers not responding

ThomasRed20

New Pleskian
Server operating system version
Ubuntu 22.04.1 LTS
Plesk version and microupdate number
Plesk Obsidian v18.0.48_build1800221104.03 os_Ubuntu 22.04
Hello,
We have been struggling to get the DNS servers working. After transferring the files from a cPanel instance to Plesk, the domain I use doesn't seem to be able to resolve. The servers are able to be resolved at the parent level, so my domain registrar has set the records correctly. (As seen below on intodns)
1673993230788.png

However, the DNS server doesn't seem to be replying with any DNS records. (As seen below on intodns)
1673993324377.png

However, the DNS server does seem to be running, as if I query the DNS server directly, the server does reply with the correct records. Using an NSLookup on the server, and a dig from another machine addressing the IP address directly, this works and gives the correct DNS records for the domain. I'm now lost for solutions on why this isn't working.

Any help would be massively appreciated.
 
Are you by chance using the same domain name for your nameserver(s) that you are hosting on that very host where bind (Plesk DNS) is hosted? The Glue error indicates that. The problem in that case is that your nameservers need to resolve themselves, but if the Glue is missing, they cannot do that, because they do not know themselves. Please see this article and comments on it. You'll probably need to add glue records:
 
Huh? I thought that was implicit on the same server and you only need glue on the servers that delegate further down, so the querying resolver can find that delegated server?
 
It is a bit unclear what the situation is, but you need the "NS" records in the DNS records of the domain if the domain itself is the nameserver name. According to the initial post screenshots these are missing.
 
Checking the DNS config, it does seem that the records in the domain are setup correctly with relavent A records for GLUE. I've attached a screenshot of the relevant DNS config in Plesk.
1674059340677.png
 
According to "intoDNS" you have a third nameserver entry that is not defined in the Plesk configuration ("snake"). This either needs to be added to the Plesk nameserver configuration or your domain provider must remove that non-existent nameserver from the domain record.

Further, I am not sure if that solves the issue, because DNSViz | A DNS visualization tool seems to have trouble connecting through UDP at all. Are you sure that the Plesk firewall allows traffic to and from your nameserver? Does the firewall that may exist in your data-center?
 
According to "intoDNS" you have a third nameserver entry that is not defined in the Plesk configuration ("snake"). This either needs to be added to the Plesk nameserver configuration or your domain provider must remove that non-existent nameserver from the domain record.
I essentially added this attempting to work out if it was just ns1, ns2 etc that was causing the problem, I'll remove that, but it wasn't working before I added this.
Further, I am not sure if that solves the issue, because DNSViz | A DNS visualization tool seems to have trouble connecting through UDP at all. Are you sure that the Plesk firewall allows traffic to and from your nameserver? Does the firewall that may exist in your data-center?
This was the issue I thought had boiled it down to previously, however, looking at a nslookup (or dig), it seems that if I query the records from my DNS server directly, it is able to reply with functioning DNS records. This is where I've got stuck previously, as it seems it both is able to reply to me for DNS records, but it doesn't seem to be able to reply to other web lookups. I'm not too sure what could be causing the issue at that point.
1674067617327.png
 
Never mind, I've just found out OVH has a pretty well-hidden "Game" firewall in addition to their normal firewall. Even though it was showing as "available", that apparently means it's on :D

Thanks for your help, your mentioning of the firewall meant I dug into OVH's terrible firewall pages to notice the second firewall.
 
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