Re: [exim-dev] Default received_headers_max should be increa…

First up: looks like we had a moderation backlog, and new subscribers
are moderated by default, so your message was stuck in moderation for
far longer than normal. Sorry about that. Your moderation bit has been
cleared.

On 2020-11-27 at 15:13 +0000, Ian Jackson via Exim-dev wrote:
> +--------------------------------------------------------+
> |received_headers_max|Use: main|Type: integer|Default: 30|
> +--------------------------------------------------------+

> I suggest that the limit should be raised to, let us say, 100.

RFC 5321 section 6.3 agrees with you.

30 has served us well for some time and I don't think it's scaling quite
that pessimistically: mail routing tends to be _simpler_ in many flows
than it was years ago, as borders mail directly to each other, while
chained mailing-lists are rare. Thus there's usually two administrative
domains to care about, or three with a mailing-list in there.

Your points about the increased complexity _within_ an ADMD,
particularly with outsourcing of some components, are sound.

I myself have only ever seen 30 reached when there's been a loop, but
raising the default to 100 is reasonable IMO.

Anyone object? Basis for objection? If objecting, alternative
proposal?

-Phil