Sorry. This comment was a bad Idea as other domains with IPs not using the "main" IP wern't able to send mail.

So better do not read further :-)

Has anybody an idea how to do the settings that there are no problems with Spamfilters?

---------do not use this it screws things up. Sorry -------- 

I did my installation with this tutorial.

After I added some more IPs to the server I suddenly had the problem that most of my mails where marked as spam by some providers (gmx for example). They did not pass the SPF Test.

After setting

inet_interfaces = <main ip adress of my server>

the problem seems to be gone. It seemd that postfix alway used the last adress set in /etc/network/interfaces.

So maybe it could be better setting  

postconf -e 'inet_interfaces = 192.168.0.100'

insted of

 postconf -e 'inet_interfaces = all'

Or may there be other problems? 

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