DNS (Domain Name System) is the internet's phone book. It translates human-readable domain names (like example.com) into IP addresses (like 192.168.1.1) that computers use to communicate.
How DNS Works
- You type www.example.com in your browser
- Your computer asks a DNS server: "What is the IP for example.com?"
- The DNS server responds: "192.168.1.1"
- Your browser connects to 192.168.1.1
- The website loads
DNS Hierarchy
DNS is a hierarchical system:
| Level | Example | Purpose |
|---|---|---|
| Root | . (dot) | Top of DNS hierarchy |
| TLD | .com, .net, .org | Top-level domains |
| Domain | example.com | Your registered domain |
| Subdomain | www.example.com | Prefix to your domain |
Key DNS Terms
- Nameserver: Server that stores DNS records for domains
- DNS Record: An entry that maps a name to a value (IP, hostname, etc.)
- TTL (Time to Live): How long DNS info is cached
- Propagation: Time for DNS changes to spread globally
- Zone: A portion of the DNS namespace managed together
Common DNS Record Types
| Record | Purpose | Example |
|---|---|---|
| A | Maps domain to IPv4 address | example.com > 192.168.1.1 |
| AAAA | Maps domain to IPv6 address | example.com > 2001:db8::1 |
| CNAME | Alias to another domain | www > example.com |
| MX | Mail server for domain | mail.example.com |
| TXT | Text information (SPF, verification) | v=spf1 include:... |
| NS | Nameservers for domain | ns1.sameservers.com |
Why DNS Matters
- Without DNS, you would need to remember IP addresses
- DNS controls where your website and email go
- Misconfigured DNS = website and email not working
- DNS is critical for security (SPF, DKIM, DMARC)
Ahosting Nameservers
To use Ahosting DNS, point your domain to:
ns1.sameservers.com ns2.sameservers.com
ns3.sameservers.com
Change nameservers at your domain registrar.