Which of the following DNS records could be a glue record?
Which of the following DNS records could be a glue record?
A glue record is used to solve circular dependencies in DNS resolution by providing an IP address for the nameserver within the parent's zone. This IP address (A record) helps in resolving the domain name of the nameserver itself. Option A shows an A record for ns1.lab pointing to the IP address 198.51.100.53, which is characteristic of glue records, as they provide an IP for a specific nameserver within the zone.
Glue records are needed to prevent circular references. Circular references exist where the name servers for a domain can't be resolved without resolving the domain they're responsible for. For example, if the name servers for yourdomain.com are ns1.yourdomain.com and ns2.yourdomain.com, the DNS client would not be able to get to either name server without knowing where yourdomain.com is. But this information is held by those name servers! This is where glue records are used. A glue record is a hint that is provided by the parent DNS server. In the case of yourdomain.com, the .com GLTD (Global Top Level Domain) servers would provide the glue records. The glue records are simply additional A records that are returned with the DNS response. These additional A records allow the DNS client to locate the name servers.
Ahhh, at last understood ! Thx. Better than my Tutor on this one :)
so to conclude , the true answer is A
answer is A