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I was running a quick check on Pingdom.com for a new website/server setup and have run into these two errors for the name servers:

Missing glue at child: ns1.MYDOMAIN.co.uk
The IP address of the name servers was not found at the child. This is a configuration error and should be corrected as soon as possible.

Missing glue at child: ns2.MYDOMAIN.co.uk
The IP address of the name servers was not found at the child. This is a configuration error and should be corrected as soon as possible.

The domain is with Godaddy, server is elsewhere, and the website resolves just fine. I am wondering if i'm missing a DNS configuration maybe?

3 Answers 3

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What they mean is that you are missing the so named glue records.

A glue record is the ip address of a name server held at the domain name registry. These are used to avoid some circular dependencies in name resolving.

Here's an example, from the wikipedia page:

Name servers in delegations are identified by name, rather than by IP address. This means that a resolving name server must issue another DNS request to find out the IP address of the server to which it has been referred. If the name given in the delegation is a subdomain of the domain for which the delegation is being provided, there is a circular dependency. In this case the nameserver providing the delegation must also provide one or more IP addresses for the authoritative nameserver mentioned in the delegation. This information is called glue. The delegating name server provides this glue in the form of records in the additional section of the DNS response, and provides the delegation in the answer section of the response.

For example, if the authoritative name server for example.org is ns1.example.org, a computer trying to resolve www.example.org first resolves ns1.example.org. Since ns1 is contained in example.org, this requires resolving example.org first, which presents a circular dependency. To break the dependency, the nameserver for the org top level domain includes glue along with the delegation for example.org. The glue records are address records that provide IP addresses for ns1.example.org. The resolver uses one or more of these IP addresses to query one of domain's authoritative servers, which allows it to complete the DNS query.

Hope this helps!

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You need to make sure the nameservers ns1.MYDOMAIN.co.uk and ns2.MYDOMAIN.co.uk answer authoritatively for themselves. For each nameserver to which a domain is delegated there must exist authoritative A or AAAA records for those nameservers. The addresses in glue records are not authoritative and do not fulfill this requirement.

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Although you name it an 'error' (with quotes) it in deed is just a notice. If the glue truly was missing, then your website would impossible work. In the past .de's would not be activated in such condition, but they policy is less strict now. And .fi's are still regularly checked by the registry. Any decent registry would not allow glue'less delegations at registration. And more important: you should never provide glue for out-of-zone nameservers (though most registries ask for it - but operationally ignore it). Just don't give it, then you know a little more sure they won't mess things up. You can enable automatic glue processing in you nameservers configuration, such that the glue would be provided as additional answer, preventing another separate query (before the DNS resolver can provide information to the end user). For hosting providers this may not be the most extreme efficient (but still faster), but for TLD's it if useful and will ease the load.

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