DNS Record Misconfiguration
DNS record misconfigurations occur when DNS records contain incorrect values, conflicting entries, or missing required records. This can cause websites to be unreachable, email delivery to fail, or services to point to wrong servers. Common mistakes include CNAME conflicts with other record types, missing MX records, and incorrect A record IP addresses.
Symptoms
- Website returns "server not found" or wrong content
- Email bounces with "no MX record" errors
- CNAME record conflicts causing resolution failures
- Subdomains pointing to decommissioned servers
Common Causes
- Incorrect IP address in A or AAAA records
- CNAME record at zone apex (not allowed by RFC)
- Missing or incorrect MX records after migration
- Duplicate or conflicting record entries
- Stale records pointing to old infrastructure
Step-by-Step Troubleshooting
- 1
Dump all DNS records
Get a complete view of all DNS records for the domain to identify conflicts and missing entries.
Use DNS Records Dump → - 2
Verify A/AAAA records
Confirm that A records point to the correct server IP addresses.
Use A Record Lookup → - 3
Check MX records
Verify MX records point to valid mail servers with correct priority values.
Use MX Record Lookup → - 4
Validate CNAME records
Ensure CNAME records don't conflict with other record types at the same name.
Use CNAME Lookup → - 5
Run WHOIS to confirm nameservers
Verify the domain is using the correct authoritative nameservers.
Use WHOIS Lookup →
Recommended Diagnostic Tools
Monitor DNS Records
Get alerted when DNS records change unexpectedly.