Fred Baker wrote:
So I have a dumb question. Why not:- use a DNS lookup that asks for all records (including A, MX, and AAAA)- open both a v4 and a v6 connection simultaneously - accept the first to successfully open and shut down all othersDown sides: It gets all of the DNS data, which may be more than it wanted to know, and it issues a second SYN-or-whatever, and in the worst case one to each address. But it deterministically finds a solution that works and gives the system the service it is looking for.I the big picture, the problem with that behavior is what?
In the big picture, I think that's the direction we need to move.But I don't think we want to have every application have that logic, since the logic might need to evolve over time (and needs to take into account Alain's example of umpteen different IP addresses - might want to stagger the attempts when there are lots of IP addresses to try.)
So instead I think we want to raise the abstraction layer for the applications by introducing a connect-by-name socket API so that the application just hands in the FQDN and the port number to which it wants to connect.
It isn't hard to come up with an initial cut of a connect-by-name implementation entirely as a library routine (using non-blocking sockets for the connect() system calls so that multiple can be outstanding and the same time.)
Erik