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(Drawing from 1-semester CCNA course in uni) Since DNS operates over UDP, isn't the amount of data that can be safely transferred effectively bottlenecked by the smallest page size between the routers that reach your device? DNS is served in one chunk, right?

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Usually if a response is greater than 512 bytes the DNS server will renegotiate on TCP 53. Note some DNS servers might not do this, but every normal implementation does that I’m aware of.

Historically musl libc didn't support TCP DNS, but even musl supports it now [1]

[1]: https://www.theregister.com/2023/05/16/alpine_linux_318/

DNS can switch to tcp for this reason

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