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It's 2019 and we have DNS over TCP and HTTP over UDP
by slim 8y ago
It's 2019 and we have DNS over TCP and HTTP over UDP
- drudru11 8y agoLol - best HN reply I’ve read in a while
- wahern 8y agoDNS has always been available over TCP. The DNS packet header has a Truncated (TC) bit that tells you when you should query over TCP, as UDP responses are usually truncated at ~500 bytes. DNS over TCP can often provide better throughput and lower latency, especially on networks with a lot of packet loss (which can be your network if you're, say, batch resolving IP address PTR records from a log where your DNS UDP requests overflow the kernel and NIC TX buffers).