DNS Tools
Use this section when name resolution, authoritative records, or propagation timing look suspicious. These pages focus on practical DNS debugging rather than just raw record dumps.
When to use this category
- A hostname resolves differently across regions or resolvers.
- MX, TXT, CAA, or NS changes do not appear when expected.
- Reverse DNS or delegation issues affect mail and trust decisions.
What you get from these pages
- Clear interpretation of record behavior and mismatch scenarios.
- Guidance for distinguishing cache delay vs. true misconfiguration.
- Direct links to adjacent checks such as RDAP, ping, and TLS tests.
Operator tips
- Capture TTL values during incidents so timing assumptions are explicit.
- Compare at least two resolver perspectives before changing production DNS.
- Treat delegation and SOA drift as high-priority control-plane risk.
Tools in this category
Frequently asked questions
Why can DNS look healthy for one user and broken for another?
Recursive resolver cache state, DNS policy, and geo-based response shaping can differ per user path.
Should I flush caches immediately after every DNS change?
Only when necessary. First confirm whether observed delay is inside expected TTL windows.
Are DNS category pages intended for beginners?
Yes. Explanations are written for both experienced operators and engineers debugging DNS less frequently.
Do these tools modify DNS records?
No. All DNS pages are read-only diagnostics.
What is the fastest follow-up when DNS appears correct?
Run HTTP header and TLS checks to verify application-layer behavior over the resolved endpoint.