DNS Management Complete Guide

DNS (Domain Name System) connects domain names to IP addresses. This guide explains DNS and how to manage your records.

What is DNS?

DNS is like the phonebook of the internet. It translates human-readable domains (google.com) into IP addresses (172.217.14.206) that computers use.

How it Works:

1. You type www.example.com in browser
2. Browser asks DNS server for IP address
3. DNS returns 192.0.2.1
4. Browser connects to 192.0.2.1
5. Website loads

Common DNS Records

A Record

• Purpose: Points domain to IPv4 address
• Example: example.com → 192.0.2.1
• Used for: Main website, pointing domain to server
• TTL: Usually 3600 seconds (1 hour)

AAAA Record

• Purpose: Points domain to IPv6 address
• Example: example.com → 2001:0db8:85a3::8a2e:0370:7334
• Used for: IPv6-enabled servers

CNAME Record

• Purpose: Creates alias for another domain
• Example: www.example.com → example.com
• Used for: Subdomains, CDN configuration
• Cannot: Be used for root domain (@)

MX Record

• Purpose: Directs email to mail server
• Example: example.com → mail.example.com (Priority: 10)
• Used for: Email routing
• Priority: Lower number = higher priority

TXT Record

• Purpose: Stores text information
• Used for:
  • SPF records (email authentication)
  • DKIM records (email signing)
  • Domain verification (Google, Facebook)
  • DMARC policies

Managing DNS Records

Via Domain Registrar

1. Log into domain registrar account
2. Find 'DNS Management' or 'DNS Settings'
3. Click 'Manage DNS Records' or 'Advanced DNS'
4. Add/Edit/Delete records
5. Save changes
6. Wait for propagation (5 minutes - 48 hours)

Via Hosting Provider

1. Update nameservers at registrar to host's nameservers
2. Log into hosting cPanel
3. Go to 'Zone Editor'
4. Manage records
5. Changes effective within 1-24 hours

Common DNS Configurations

Point Domain to Hosting

Type: A\nName: @\nValue: 192.0.2.1 (your server IP)\nTTL: 3600

Point WWW to Main Domain

Type: CNAME\nName: www\nValue: example.com\nTTL: 3600

Set Up Email

Type: MX\nName: @\nValue: mail.example.com\nPriority: 10\nTTL: 3600

DNS Propagation

What is it? Time for DNS changes to spread worldwide.

Timeline:

• Local DNS servers: 5 minutes - 1 hour
• Regional DNS servers: 2-24 hours
• Global propagation: Up to 48 hours

Check Propagation:

• whatsmydns.net
• dnschecker.org
• Shows DNS status worldwide

TTL (Time To Live)

What is TTL? How long DNS records are cached.

• High TTL (86400 = 24 hours):
  • Faster lookups (cached longer)
  • Slower to update
  • Use for stable sites
• Low TTL (300 = 5 minutes):
  • Slower lookups
  • Faster updates
  • Use before migrations

DNS Security

• DNSSEC: Adds authentication to DNS
• Enable at registrar: Prevents DNS hijacking
• Use CloudFlare: Additional DDoS protection
• Monitor changes: Get alerts on DNS modifications

Troubleshooting DNS