On Thu, Jun 10, 2021 at 02:59:02AM +0000, Apelin, Eulogio wrote:
> I am testing my mail server setup, when telnetting to port 25, I receive this
> interaction when I type 'helo myserver.com'
>
> 220 *******************************************************************
This banner typicall results from a Cisco ESA firewall with SMTP
inspection enabled that is located between client and server.
The Cisco ESA adds no value in front of Postfix, just breaks SMTP.
Disable SMTP inspection on that device.
--
Viktor.
