Feature #9925
Updated by nobu (Nobuyoshi Nakada) over 10 years ago
In ext/socket/raddrinfo.c, the function `rsock_addrinfo()` rsock_addrinfo() always uses `AF_UNSPEC` AF_UNSPEC for DNS queries. This is causing me a very high volume of IPv6 DNS lookups. `rsock_addrinfo()` rsock_addrinfo() is used by TCPSocket (and all other Socket base classes, e.g. Socket and UDPSocket), and TCPSocket is used by Net::HTTP. Remember that DNS does not do negative caching - if a hostname does not have a AAAA record, then DNS will _always_ try to look up that record again! I propose that the following code should have some way to force IPv4 or IPv6 lookups: http://rxr.whitequark.org/mri/source/ext/socket/raddrinfo.c ~~~c 378 struct addrinfo* 379 rsock_addrinfo(VALUE host, VALUE port, int socktype, int flags) 380 { 381 struct addrinfo hints; 382 383 MEMZERO(&hints, struct addrinfo, 1); 384 hints.ai_family = AF_UNSPEC; 385 hints.ai_socktype = socktype; 386 hints.ai_flags = flags; 387 return rsock_getaddrinfo(host, port, &hints, 1); 388 } ~~~ For example, an environment variable named something like `RUBY_GAI` RUBY_GAI could be set to "INET" or "INET6" to switch the `hints.ai_family` hints.ai_family away from `AF_UNSPEC`. AF_UNSPEC.