// dns · a
io9.com A Record Lookup
Use this A record lookup tool to find the IPv4 addresses for io9.com. A records map a domain name to its IP addresses: when your browser connects to io9.com, it retrieves these A records first.
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What Is io9.com's IP Address?
An A (Address) record maps io9.com to a 32-bit IPv4 address. When you type io9.com into your browser, the first step is a DNS lookup that returns these A records. The IP addresses your browser connects to in order to load the website.
io9.com may have one or multiple A records. A single A record means all traffic goes to one server, while multiple A records typically indicate load balancing or CDN usage, distributing visitors across several servers for better performance and reliability.
io9.com's A records are the current IPv4 addresses that the domain resolves to. These can change if io9.com switches hosting providers, adds a CDN, or updates its server infrastructure.
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What Are A Records?
A records are the most fundamental DNS record type. They provide the direct mapping between a human-readable domain name like io9.com and the machine-readable IPv4 address that computers use to route network traffic. Without A records, browsers would have no way to find the server hosting io9.com's website.
Each A record has a TTL (Time To Live) value that tells DNS resolvers how long to cache the result. A short TTL means changes propagate quickly but generate more DNS queries. A long TTL reduces DNS traffic but means changes take longer to take effect. io9.com's A records each carry their own TTL value.
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A Records vs AAAA Records
A records hold IPv4 addresses (32-bit, e.g., 192.0.2.1), while AAAA records hold IPv6 addresses (128-bit, e.g., 2001:db8::1). Both serve the same purpose (mapping io9.com to an IP address), but for different versions of the Internet Protocol.
IPv4 addresses are limited to about 4.3 billion unique addresses, which have been fully allocated. IPv6 provides a vastly larger address space. Modern domains like io9.com ideally support both protocols. Check io9.com's IP address page to see if it has IPv6 support.
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Multiple A Records and Load Balancing
When an A record lookup for io9.com returns multiple addresses, DNS resolvers typically rotate them in round-robin fashion. This distributes traffic across several servers without requiring a dedicated load balancer. CDN providers like Cloudflare, Fastly, and AWS CloudFront use this technique extensively.
If io9.com uses a CDN or cloud hosting, its A records may point to different IP addresses depending on the geographic location of the DNS resolver. This is called GeoDNS or anycast routing, and it ensures visitors connect to the nearest server for optimal performance.
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Frequently Asked Questions
What IP address does io9.com resolve to?, io9.com's A records list all IPv4 addresses that the domain currently resolves to. Each address represents a server that can handle requests for io9.com.
Does io9.com use multiple IP addresses?. If more than one A record exists for io9.com, then yes. The domain uses multiple IP addresses, likely for load balancing, redundancy, or CDN distribution.
What is a DNS A record?. An A record is a DNS entry that maps a domain name to an IPv4 address. It's the most basic DNS record type and is essential for any domain to be reachable on the web.
How do I find who hosts io9.com?. You can perform a reverse IP lookup on io9.com's IP addresses, or check the WHOIS page for io9.com to find registration and hosting information.