DNS Troubleshooting Basics
A beginner-friendly guide to DNS checks for website and login issues.
DNS maps names to destinations
DNS helps turn a domain name into the records browsers and services use to connect. When DNS is wrong or stale, a site may fail before the app is even reached.
Check the symptom
Does the domain fail for everyone, one network, one region, or one machine? Scope helps separate local cache issues from broader DNS problems.
Review recent changes
DNS issues often follow domain moves, record edits, certificate changes, or provider migrations. Propagation can also make behavior inconsistent for a while.
Keep notes precise
Record the domain, timestamp, resolver, network, error message, and commands or tools used to inspect records.
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Small utilities for the next step
Severity / Priority Calculator
Use it before filing a defect, during triage, or when a team needs a quick neutral starting point.
Incident Timeline Builder
Use it during bug escalations, support handoffs, launch issues, or post-incident summaries.
Timestamp Converter
Use it when comparing log entries, user reports, screenshots, and monitoring events.
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