EMZETT.A Record
In short: A DNS record type that directly maps a domain name to an IPv4 address.
In more detail: The A record (“Address Record”) is the most basic DNS record type — it answers the question “which IP address belongs to this name?” for IPv4. For IPv6 addresses, the AAAA record handles the same task instead.
In Depth
Structure
An A record consists of four parts: name, type (A), TTL, and value (the IPv4 address).
emzett-digital.com. 3600 IN A 76.76.21.21
The trailing dot after the domain name marks the root domain and is usually omitted in tools, but is technically the actual root node of the DNS hierarchy — without it, the name would theoretically be ambiguous (relative instead of absolute). The 3600 is the TTL in seconds — here one hour, before a resolver has to query the value again. The IN stands for “Internet” and is a historical relic from a time when DNS was also intended for other network classes (e.g. Chaosnet) — today practically always IN, but remains a mandatory field in the zone-file format for compatibility reasons.
Multiple A records and round-robin DNS
A domain can have several A records at once (several IP addresses for the same name). Clients then usually pick one randomly or in turn (“round-robin DNS”) — a simple but crude approach to load distribution without real load balancing. The decisive difference from real load balancing: DNS knows nothing about the current load of the servers behind it and can’t automatically react if a server fails, until someone manually removes the affected record (or a specialised “health-check DNS” service handles it). For this reason, round-robin DNS in modern setups is usually only used for rough geographic distribution (e.g. different IPs depending on the region of the requesting resolver, “GeoDNS”), while the actual load distribution within a region is handled by a real load balancer.
Interaction with CNAME
If the A record is completely missing but a CNAME record exists, its target is resolved instead — but according to the standard, CNAME and A must not exist for the same name at the same time. This is exactly why many DNS hosts offer a proprietary alternative like “ALIAS” or “ANAME” for the root domain (which technically isn’t allowed to have a CNAME), which behaves like a CNAME for the user but is internally resolved server-side to a matching A record before the response is sent.
Practical debugging
With dig (Linux/macOS) or nslookup/Resolve-DnsName (Windows), an A record can be queried directly:
$ dig emzett-digital.com A +short
76.76.21.21
If the returned IP differs from what’s expected, it’s usually either a not-yet-expired cache entry (wait until the TTL expires) or a sign that the change was made in the wrong place (e.g. at the registrar instead of the DNS host actually delegated to via an NS record).
See also: DNS Records, AAAA Record, IPv4