Sahil Tandon:
> > Sahil Tandon:
> > > FWIW, the FreeBSD Postfix port is patched so that post-install does not
> > > add "inet_protocols=ipv4" to main.cf during upgrades. Instead, users are
> > > notified[1] about the recent change of defaults, and asked to append the
> > > ipv4 line to their main.cf, if necessary.
> >
> > Sorry, THAT IS A MISTAKE.
> >
> > Sites that already Postfix have already chosen what protocols
> > they use. They must not be forced to take action when upgrading.
> > FORCING SITES TO CHANGE CONFIGURATION AFTER UPGRADE IS A MISTAKE.
>
> The distinction is mostly semantic and tangential to the main
> discussion, but for completeness: users are supposed to consult
> ports/UPDATING before (not after) upgrading.
Sites that use Postfix 2.8 without IPv6 have no inet_protocols
setting in main.cf. They have never needed one because that was the
default. Having to add "inet_protocols = whatever" for Postfix
2.9 is an unnecessary compatibility break that can be avoided.
Sites that currently rely on the default (no IPv6) must not experience
a compatibility break just because the built-in default was changed.
It is a major mistake at this time to turn on IPv6 in Postfix by
default, because it will suck performance for the far majority of
sites with useless DNS lookups and useless connection attempts.
This is harmful for Postfix market share.
Unlike some open source products, I plan incompatible changes very
carefully. Where this is possible, this goes as follows:
1) First I change the built-in default; at the same time post-install
is changed to make a compatibility update to main.cf that restores
the old default, for sites that have relied on the old default.
2) Several years later, I remove the post-install code.
If you cannot respect my effort to avoid incompatible changes, then
I will revert the change of the inet_protocols default value and
go back to Postfix 2.8 behavior. This means that people such as
Mark Martinec wil have to jump some extra hoops when they wish to
compile in an ipv4-less build environment. That is still better
than having Postfix ruined by a maintainer who does not respect my
attempts to phase in a major change with a great deal of care.
Wietse
