Brutkey

Alex 🔜🔜 FOSDEM
@alexhaydock@infosec.exchange

Everything I've read suggests #musl resolv.conf only supports 3 nameservers in resolv.conf.

So why does dnscheck.tools suggest that all 6 of the resolvers I configured are actually working?

😵‍💫😵‍💫 Very puzzling

An excerpt from https://wiki.musl-libc.org/functional-differences-from-glibc.html#Name-Resolver/DNS It reads: "Traditional resolvers, including glibc’s, make use of multiple nameserver lines in resolv.conf by trying each one in sequence and falling to the next after one times out. musl’s resolver queries them all in parallel and accepts whichever response arrives first. This can increase network load (this is mitigated by only supporting up to three nameservers, and can be mitigated further at the configuration level by only configuring one nameserver) but drastically improves performance and reliability of DNS lookups, especially if diverse nameservers are used." A screenshot of the resolv.h source code with the line highlighted "#define MAXNS 3" My resolv.conf showing 6 upstream IPv6 DNS servers being configured A screenshot from dnscheck.tools showing all 6 of the configured resolvers in resolv.conf actively resolving my DNS queries