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At midnight UTC on New Year’s Day, deep inside Cloudflare’s custom RRDNS software, a number went negative when it should always have been, at worst, zero. A little later this negative value caused RRDNS to panic.
We launched DNSSEC late last year and are already signing 56.9 billion DNS record sets per day. At this scale, we care a great deal about compute cost.
The Go test coverage implementation is quite ingenious: when asked to, the Go compiler will preprocess the source so that when each code portion is executed a bit is set in a coverage bitmap.
Hi, I'm Filippo and today I managed to surprise myself! (And not in a good way.) I'm developing a new module ("filter" as we call them) for RRDNS, CloudFlare's Go DNS server.
Here at CloudFlare we are heavy users of the github.com/miekg/dns Go DNS library and we make sure to contribute to its development as much as possible. Therefore when Dmitry Vyukov published go-fuzz and started to uncover tens of bugs in the Go standard library, our task was clear.
CloudFlare’s DNS server, RRDNS, is entirely written in Go and typically runs tens of thousands goroutines. Since goroutines are cheap and Go I/O is blocking we run one goroutine per file descriptor we listen on and queue new packets for processing.
CloudFlare's DNS server, RRDNS, is written in Go and the DNS team used to generate a file called version.go in our Makefile. version.go looked something like this.
Something that often, uh... bugs Go developers is the lack of a proper debugger. Builds are ridiculously fast and easy, but sometimes it would be nice to just set a breakpoint and step through that endless if chain or print a bunch of values without recompiling ten times.
A cornerstone of CloudFlare's infrastructure is our ability to serve DNS requests quickly and handle DNS attacks. To do both those things we wrote our own authoritative DNS server called RRDNS in Go.
Almost two years ago CloudFlare started working with Go. What started as an experiment on one network and concurrency heavy project has turned into full, production use of Go for multiple services.
About a year ago, we realized that CloudFlare's current DNS infrastructure had some challenges. We were using PowerDNS, an open source DNS server that is popular with hosting providers.
CloudFlare runs one of the largest networks of DNS servers in the world. Over the last few months, we've invested in making our DNS as fast and responsive as possible. We were happy to see these efforts pay off in third-party DNS test results.
