Configuring DNS Records via Registrar and DNS Hosting

DNS (Domain Name System) is a system that translates human-friendly domain names (e.g., example.com) into computer-readable IP addresses. Without proper DNS configuration, your website, email, or other services will simply not function.

The Role of DNS: DNS links your domain to servers hosting your data. For example, when a user enters a website address, DNS directs the browser where to find it.

Consequences of Errors: Incorrect settings can cause website downtime (e.g., if an A-record points to the wrong IP) or email loss (if MX records are misconfigured).

Primary Use Cases:

• Linking a domain to web hosting for site accessibility
• Configuring corporate email (e.g., via Gmail or Yandex.Mail)
• Connecting CDNs (e.g., Cloudflare) for acceleration and security
• Creating subdomains (e.g., blog.example.com)

Registrar vs. DNS Hosting: Registrar is the company where you purchase domains (e.g., Reg.ru). DNS hosting is a service managing your DNS records. Registrars often provide basic DNS hosting, but third-party services (e.g., Cloudflare) can be used.

NS Servers and DNS Zone: NS servers (Name Servers) store your domain's DNS records. DNS zone is the complete set of records for a domain.

TTL (Time to Live): Duration (in seconds) DNS records are cached. Low TTL (300-600 sec) speeds up updates; high TTL (86400 sec) reduces server load.

Preparation

Gathering Required Information

Before configuration, collect:

• Server IPs: Web server IP (for A-records) and mail server IPs (for MX records)
• Email Data:
  • MX records (pointing to mail servers)
  • SPF, DKIM, DMARC (for spam/spoofing protection)
• CNAME: Required for CDNs or external services (e.g., analytics)
• Current Record Check: Use nslookup example.com or dig A example.com to verify existing settings

Strategy Selection

• Registrar vs. Third-Party DNS: Registrar DNS is user-friendly, but third-party services (Cloudflare, Yandex) offer DDoS protection and analytics
• When to Change NS Servers: Switch to external DNS hosting for advanced features (e.g., geo-routing or dynamic IP updates via API)

Step-by-Step Record Configuration via Registrar

Accessing Control Panel

• Interfaces: Each registrar has its own panel (Reg.ru, Nic.ru, GoDaddy, Namecheap). Look for "DNS Management" or "Zone Editor"
• Where to Find: Search for "DNS Records" or "Zone Editor" tab

Key Record Types (with Examples)

Practical Cases

1. Linking Domain to Hosting:

• Add A-records for @ (root domain) and www with your server's IP
• Example: @ A 192.0.2.1 and www A 192.0.2.1

2. Gmail/Yandex.Mail Setup:

3. Connecting Cloudflare:

• Replace NS servers with Cloudflare's (e.g., ns1.cloudflare.com)
• Cloudflare auto-imports existing records

Special Settings

• Wildcard Records: *.example.com handles all subdomains without explicit records. Individual subdomain records (e.g., blog.example.com) take priority
• Redirects: Some registrars support URL redirects in their panels
• Subdomains:
  • mail.example.com - for email
  • cdn.example.com - for static files

Working with DNS Hosting (Cloudflare, Yandex)

Transferring DNS Management

• Changing NS Servers: Update NS servers in registrar's panel
• Propagation Time: Changes typically take hours but may require up to 48 hours globally

Benefits of External DNS Hosting

• DDoS protection (Cloudflare filters malicious traffic)
• DDNS (API support for dynamic IP updates)
• Geo-routing (traffic directs to nearest server)
• Analytics (DNS query statistics)
• Encryption (DoH/DoT support)

Advanced Configuration

• DNSSEC (prevents record tampering)
• Rewrite rules (configure redirects at DNS level)
• TTL management (lower before changes for faster updates)

Verification and Testing

Validation Tools

• Online Services: DNSCHECKER, MXToolbox
• Commands:
  nslookup example.com
  dig A example.com +short
  dig MX example.com

Common Errors

• Missing trailing dot (use example.com.)
• CNAME conflict (can't coexist with other records)
• MX priority (lower number = higher priority)
• Caching (old records persist due to TTL)

Validation Checklist

• A-records point to correct IPs
• MX records match email provider
• TXT records (SPF/DKIM/DMARC) are valid
• HTTPS works without errors (verify domain in certificate)

Security and Optimization

DNS Protection

• 2FA (enable two-factor authentication)
• Access restrictions (allow logins only from trusted IPs)
• Audits (regularly review for outdated records)

Performance Optimization

• TTL (low: 300-600 sec for dynamics; high: 86400 sec for static)
• Anycast DNS (accelerates responses via distributed servers)
• Caching (use resolvers to reduce load)

Common Issues & Solutions

1. Website Unavailable:

• Verify NS servers
• Wait for propagation (4-12 hours typically; up to 48 hours)

2. Email Delivery Failure:

• Check SPF/DKIM/DMARC
• Ensure IP isn't blacklisted (Spamhaus)

3. SSL/TLS Errors:

• Confirm domain name matches certificate
• Renew certificates (e.g., Let's Encrypt)

Key Recommendations:

• Back up zone before changes
• Use external DNS hosting for critical projects
• Update records for dynamic servers via API regularly

Additional Resources:

• SPF/DKIM/DMARC generators (mxtoolbox.com)
• DNS monitoring (UptimeRobot)
• Migration tools (Cloudflare Transfer)

Proper DNS configuration is like a building's found