DNS Propagation Explained: Why Different Lookups Can Show Different Answers
Why can two people see different results after a DNS update? Cached answers and delegation changes can take time to be reflected.
1:47 · No narration: the video shows each step as text on screen, and every step is written out below, with buttons that jump the video to it.
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The six points in the video
This is a silent video. The headings, explanations and labels below reproduce the information on screen.
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Step 1: Confirm the authoritative source
Check which provider currently answers for the domain.
On-screen labels: Delegated nameservers; Active DNS zone; Current provider.
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Step 2: Verify the new value first
Waiting will not fix an incorrect address or a record in the wrong account.
On-screen labels: Correct record name; Correct value; Correct DNS account.
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Step 3: Check the previous cache lifetime
Existing cached answers can remain while their lifetime runs down.
On-screen labels: Previous record; Cached value; Remaining lifetime.
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Step 4: Delegation is another change
Moving nameservers also changes where answers are obtained.
On-screen labels: Nameserver change; New record set; Delegation status.
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Step 5: Test the affected services
Website access and business email need their own checks.
On-screen labels: Website destination; Incoming email; Other connected services.
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Step 6: Keep a useful change record
Record when the update happened and the values that were checked.
On-screen labels: Change time; Observed answers; Provider support evidence.
A practical check for your business
Record the old answer, new answer and time of the authorised DNS change. Compare authoritative information with cached results while checking the website and email tasks the business relies on.
Sources and further detail
Common questions
Why can two people see different results after a DNS update?
Cached answers and delegation changes can take time to be reflected. Distinguish an old cached answer from an incorrect current record.
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