I have access to a couple of Ubuntu servers and I am trying to configure the PHP mail() command for each of these servers. However, for one of these servers, the From: header is overwritten by www-data@. I have no access to the SPF record of that hostname, so I want to configure the mail server so it doesn't overwrite the From: header.
So my question is, how do I find out which mail server is used so I can correctly configure that mail server? (Postfix, SSMTP, ...)
Thanks in advance!
To get a list of packages installed locally do this in your terminal:
dpkg --get-selections | grep -v deinstall
To save that list to a text file called packages on your desktop do this in your terminal:
dpkg --get-selections | grep -v deinstall > ~/Desktop/packages
Then search for Mailserver. I'll do my bet for Postfix, which seems to be the most used.
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