Re: [gentoo-user] tips on running a mail server in a cheap vps provider run but not-so-trusty admins?

[Caveman Al Toraboran]

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Friday, August 21, 2020 4:28 PM, Wols Lists <antlists@××××××××××××.uk> wrote:

> You're re-inventing the wheel.

yes, i do consider re-inventing octagonal wheels.
though this wasn't my point here.

here, i'm just "asking" to see what makes the
"safely stored" guarantee.  perhaps i should've
asked more directly (and yes, i know these are not
new features).



> >     1. receipt by final mail server (mandatory).
> >
>
> This is part of SMTP already, in that each server (post office)
> acknowledges that the message has been received AND SAFELY STORED.
> Without that last guarantee, "receipt by the server" isn't worth
> diddley-squat.

got any specific definition of what makes a
storage "guaranteed"?  e.g. what kind of tests
does the mail server do in order to say "yup, i
can now guarantee this is stored safely!"?


> > the job of a relay would be to optionally add some
> > metadata (e.g. maybe describing sender's role) and
> > sign the whole thing (e.g. by company's private
> > key). this way we can have group-level rules.
>
> Except that SMTP allows for the fact that a message may (or may not)
> pass through several post-offices on the way. The old internet thing of
> "don't assume any computer will survive a nuclear attack - take whatever
> route you can find ..." so there is no guarantee that a relay going in
> one direction will even see a message going back in the other.

so?  not sure how this relates to what i said.  i
guess you think that i meant that a relay should
be mandatory?  or maybe i'm misunderstanding your
point?

(yes, a relay doesn't have to be used.  i'm just
describing some uses of relays that i think make
sense.  (1) indicate trust hierarchy, (2) offload
mail delivery so that i can close my laptop and
let the relay have fun with the retries.  not sure
there is any other use.  anyone?)