[CentOS] How to handel smtp to public servers

John R Pierce

pierce at hogranch.com
Wed Jun 27 10:02:59 UTC 2012

On 06/27/12 2:15 AM, Götz Reinicke wrote:
> Hi, thanks for your suggestion. But for the mentioned clients thats not
> possible. :/ (For our own we do exactly as you suggest :) )
> We do have about 100th of freelancers 'flying in and out' of our academy
> which we cant 'restrict' by forcing tham to change there clients settings.

MSN, gmail, etc don't accept simple port 25 SMTP from random clients, 
they only accept authenticated SSL encrypted port 465 or whatever.

so its simple, block port 25 outbound from anything but your own 

john r pierce                            N 37, W 122
santa cruz ca                         mid-left coast

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