[TUHS] Testing Mail Connectivity

[Grant Taylor]

On 6/25/19 8:50 PM, Warren Toomey wrote:
>> You need to grok Sendmail's log format (and SMTP in general), but it means 
>> that Minnie connected to my server, waited the requisite time for the greeting 
>> banner, and then shat herself when she saw my ginormous banner and dropped the 
>> connection without so much as a good-bye...
> 
> i.e.a multiline response to the HELO/EHLO which meets the RFC specs.
> 
>> That simple measure, along with the greeting pause and some simple RFC DNS 
>> checks, block a lot of the crap.

The greet pause seems longer than I'd choose, but I think it's less than 
60 seconds.  Any reasonable mail server should handle that.  So that 
shouldn't be an issue.

> I've just subscribed to the Postfix mailing list, and I'll ask on there 
> if there is a configuration change I can make to allow my Postfix client 
> to deal properly with Dave's multiline HELO/EHLO response. And why it can't 
> at present.

I'd be surprised if Minnie had a problem with the multi-line greeting.

I think Postfix (if that's what Minnie is running) has been dealing with 
multi-line greetings for a while.  There's also the fact that—I 
suspect—Minnie has been successfully delivering THUS to Dave's server 
for a while.  So unless Dave's multi-line greeting is new....

> But if someone here already knows, could they let me know?!

Do you have errors in your log?

Dave, Warren, feel free to reply to me (both of us) directly if you want 
to discuss this further off list.



-- 
Grant. . . .
unix || die

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