Routing & ResolutionRFC 1035
A Record — A Record (IPv4 Address)
Maps a human-readable domain name directly to a 32-bit IPv4 address (e.g. 192.0.2.1).
RECORD TYPE
A
STANDARD RFC
RFC 1035
DEFAULT TTL
3600 seconds (1 hour)
CATEGORY
Routing & Resolution
BIND Zone File Syntax Example
example.com. 3600 IN A 76.76.21.21How to Query & Check A Records
Linux / Mac (dig)
dig +short A example.comWindows / Generic (nslookup)
nslookup -type=A example.comPowerShell (Resolve-DnsName)
Resolve-DnsName -Name example.com -Type ARecommended Best Practices
For zero-downtime server migrations, reduce the A record TTL to 300 seconds (5 minutes) at least 24 hours prior to changing the IP address.
Primary Use Cases:
- •Pointing an apex root domain (`example.com`) to a web host or static IP
- •Configuring server IP addresses for VPS, dedicated servers, or load balancers
- •Pointing subdomains (`api.example.com`) to backend clusters
Common Configuration Mistake
Pointing an A record to a domain name instead of an IP address (use CNAME instead for domain aliases).
Always verify records using authoritative queries (`dig @1.1.1.1 $A example.com`) to bypass local ISP caching when debugging propagation delays.
Frequently Asked Questions
DNS A Record Questions & Answers
Common questions regarding DNS propagation, TTL settings, and zone file syntax.
The A (Address) record is the most fundamental DNS record on the internet. When a browser queries your website domain, the resolver looks up the A record to locate the web server or load balancer IPv4 address.