On 10.04.2015, Peter Ulrich Kruppa wrote:
>Now let's test something bad and completely turn of my
firewalld !
Turning off a netfilter/firewall for testing purposes is not necessarily bad.
That obviously works!
Here you go. Eventually, you found it!
Take a look into your firewall rules and logs to find out where it blocks.
Educated guess: port 25 presumably doesn't receive any packets..