How to prevent, or change priority, of dovecot's FAILed relay-submission to relay's IPv6 address, and submit ONLY/first to IPv4?

[@lbutlr]

On 09 Apr 2021, at 08:29, PGNet Dev <pgnet.dev at gmail.com> wrote:
> 
>>> And it's a bad assumption that since the host is dual-stack that all services on it will be.
>> If a hostname resolves to both an A and AAAA record, it should provides services on both.
> 
> Says who/what?
> 
> There is no should/must/shall in any internet standard that suggest/implies/requires that.

It's blatantly obnvisou because otherwise you have to try to figure out if www.example.com:587 is on the A or the AAAA record, which is pretty much he opposite of how multiple records work.

If you had a DNS that returned multiple IPs got ;old balancing, would it be rational to have only SOME of those IPs respond on port 587 and others respond only on port 465 or 8955?

Of course not.

If you have to mandate ipv4, use the ipv4 address.

-- 
I desire the things that will destroy me in the end.