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Q & A DNS Records · August 21, 2026

What happens if the SOA serial number doesn't increase?

Secondary nameservers compare their copy of the serial number against the primary’s. If the primary’s serial is not higher, secondaries assume they already have the latest zone data and skip the transfer. Changes to your DNS records will not propagate to secondary nameservers until the serial is incremented.

Read the full guide
What Is an SOA Record? The DNS Zone's Control File Explained
The SOA record is DNS's control file — it governs zone transfers, cache TTLs, and negative response lifetimes. Every misconfiguration here ripples across every resolver on the internet.
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