Kaare Rasmussen <kar(at)kakidata(dot)dk> writes:
> Sorry if this is obvious to you, but it's not obvious to me.
> In 7.4 this
> psql -h 127.0.0.1 test and
> psql -h localhost test
> will be authenticated as ipv6 addresses.
Only if your libc and/or kernel preferentially treats them as ipv6.
CVS tip contains a fix to allow ipv4 addresses in pg_hba.conf to match
ipv4-mapped-to-v6 ipv6 connections; this should allow people to continue
believing they are using ipv4 even when their system is mapping to v6.
regards, tom lane