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Well, I have some understanding of how DNS works, but that doesn't allow me to answer this question. It must have to do with the time to live value of each particular record. But there are a bunch of timing parameters in SOA. So I'm not sure, which of them I should consider. Also, different DNS servers may treat this values differently, I take it.

So, suppose, I'm going to change domain's: 1) IP address, 2) NS servers. Is there a way to find out how much will it take? Probably if we assume that DNS servers respect supplied parameters.

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migrated from Aug 8 '14 at 4:44

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For caching in general the TTL value of the specific record/RRset is used.

For caching of negative responses the last value in SOA (the MINIMUM field) is used.

The above applies to all records in your own zone. And with planned changes you have the ability to lower the TTL in advance (at least the old TTL in advance) to minimize the time that old data remains valid after your changes.

As for the other timing parameters of the SOA, those relate to the authoritative servers in a master/slave setup.

If you are changing the delegation, however, you do not only deal with records in your own zone but also the delegatory NS records in the parent zone as well as any glue A/AAAA records when applicable.

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So, changing A records takes its TTL values seconds? Also, could you elaborate on delegation part? It has to do with which records in the parent zone? What exactly happens there? Also, based on what do they say, that it takes 48 hours for nameserver changes to take effect, and 8 hours for A records? Why does propagation doesn't take one of those TTL values? – x-yuri Aug 9 '14 at 23:30

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