On 7 Sep 2019, at 7:10, Graeme Fowler via Exim-users wrote:
> On 7 Sep 2019, at 11:13, Cyborg via Exim-users <exim-users@???>
> wrote:
>> The question is, what is the reality?
>
> Nobody really knows.
>
> The fact that Exim is/was the default MTA in a couple of distros means
> there’s an awful lot of systems running it out there.
Another source of inflation in the Exim numbers is that it is the only
MTA available for cPanel and it is commonly up and answering at the MX
for every domain hosted on a cPanel host, even if it isn't actually
functional for the domain, with one actual Exim instance possibly
serving scores of domains that frequently have few or no real users each
but may have many users.
> But… nobody really knows for sure.
There's also a problem in how one counts "mail servers." Is that MTA
instances? Domains? Physical hosts? OS instances? What about one OS
instance running multiple independently administered MTAs? (think:
FreeBSD jails.) Is a load balanced HA cluster 1 server or many?
One of the cited sources (Security Space:
http://www.securityspace.com/s_survey/data/man.201908/mxsurvey.html)
does their survey by domain but only gets an identifying banner from 51%
of the MX records they chase. Of those, Exim is 57%. That is NOT an
unbiased sample. I can't quantify the biases but I would expect that
Exim is greatly over-represented in the "identifiable" half simply
because of the cPanel effect, which is consistent with the fact that 3/4
of the identified Exim domains are running 4.92.
--
Bill Cole
bill@??? or billcole@???
(AKA @grumpybozo and many *@billmail.scconsult.com addresses)
