agreed. and one of my mods to the ultrix (~4.3bsd) kernel for
gatekeeper.dec.com back in ~1990 was to use the result of gethostid(3)
if that result was nonzero and if a socket was not already bound. so
named(8) and ntpd(8) and anything else that used explicit binding got
what they expected, but the vast majority who just used INADDR_ANY (or
more often just bzero(3)'d the sockaddr) would get what the sysadmin
wanted. multihoming wasn't well understood and has gotten worse since.
of course, gethostid(3) is now deprecated in favour of sysctl(3), and
the hostid(8) command is gone, and there's now more than one flavour of
Internet-capable UNIX in the world, and there's more than one Internet
address family now. so what i did in 1990 is a guide only inasmuch as
some way should exist to change the default local address of a socket so
that it isn't the address of the interface used for the destination. if
that happens i hope we coordinate with Linux and with the other BSD's.
Gregory Shapiro wrote on 2024-04-24 11:00:
I still see value in source IP selection, even outside of the IX use
case.
--
P Vixie
