DNS Records Checker

Domain resolution failures typically occur due to DNS server issues, incorrect records, or cache expiration delays. Check your DNS configuration and server connectivity first.

• DNS server not responding or unreachable
• Incorrect A or AAAA records pointing to wrong IP
• DNS cache issues on your device or ISP level
• Recent DNS changes still being cached (up to 48 hours)

A records map domains to IPv4 addresses (32-bit), while AAAA records map to IPv6 addresses (128-bit). Both can coexist and clients will use the appropriate version.

• A Record: Points to IPv4 (e.g., 192.0.2.1)
• AAAA Record: Points to IPv6 (e.g., 2001:db8::1)
• IPv6 is the future but IPv4 is still widely used
• Having both ensures maximum compatibility

Use A records to point directly to IP addresses, and CNAME records to create aliases that point to other domain names. CNAME offers flexibility but has limitations.

• A Record: Direct domain-to-IP mapping
• CNAME: Alias pointing to another domain
• CNAME cannot be used for root domains (@)
• Avoid CNAME chains (CNAME → CNAME)

MX records tell email servers where to deliver mail for your domain. Lower priority numbers are preferred, and multiple MX records provide redundancy for email delivery.

• Priority values determine server preference (lower = higher priority)
• Multiple MX records provide email server redundancy
• MX records must point to A/AAAA records, not CNAME
• Incorrect MX records cause email delivery failures

TXT records store arbitrary text data, commonly used for domain verification, SPF/DKIM email authentication, and various service confirmations like Google Workspace or Office 365.

• Domain ownership verification for services
• SPF records for email sender authentication
• DKIM and DMARC for email security
• Site verification for search engines

NS records specify which DNS servers have authority over your domain. They delegate DNS control and determine where DNS queries are directed for resolution.

• NS records have ultimate control over domain resolution
• Used for subdomain delegation to other DNS providers
• Changing NS records affects all DNS records for the domain
• Propagation of NS changes can take 24-48 hours

DNS changes appear gradually worldwide due to TTL (Time To Live) caching. Each DNS server independently discovers new records when their cache expires, not through active propagation.

• TTL controls cache expiration time on DNS servers
• ISP and resolver servers discover changes independently
• Global cache expiration typically takes 4-24 hours
• Lower TTL before changes speeds up discovery

DNS resolution speed depends on your DNS provider, TTL values, and network configuration. Using fast public DNS servers and optimizing TTL values can improve performance.

• Use reliable DNS providers (Cloudflare, Google, Quad9)
• Optimize TTL values (300s for frequent changes, 3600s for stable)
• Flush local DNS cache if experiencing issues
• Consider DNS prefetching for critical domains