This feature would make it easier to run multiple nameservers on a single machine without their coming into conflict, a problem that was encountered in Ubuntu Desktop which introduced a dnsmasq process controlled by NetworkManager ( https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/959037).
As I wrote in comment #46 on that bug report, OpenBSD and Mac OS X already have this feature. Here's an extract from the OpenBSD resolv.conf man page. nameserver IPv4 address (in dot notation) or IPv6 address (in hex-and- colon notation) of a name server that the resolver should query. Scoped IPv6 address notation is accepted as well (see inet6(4) for details). A non-standard port may be specified using [host]:port syntax. That would be "[8.8.8.8]:53" for Google's nameserver. The syntax for OS X is "address.port", which would be "8.8.8.8.53" for Google's nameserver. One can also give a "port" option to select the port for nameserver options lacking a port number. We could adopt one of these syntaxes or devise another one that was entirely backward compatible. I looked at the eglibc source code and it would not be hard to implement this feature. Once can assume, however, that even if we came up with a patch today it would be years before the feature became generally available. -- Thomas
