I am asking these questions below, because aside from that I am a complete beginner on this things, I am also looking at this spf and sender id.
I did a forward dns of our host company domain which also host several domains. After getting the ip of that test, i tried to reverse dns that ip. Here are the results below of the reverse dns.
Hostname: server-center.net <--what is this domain? Is this the one hosting our main domain? Our main domain is also where emails are returned from us. Our main domain also host several domains of our company. Does the server that our domain used located at server-center.net?
For additional info, we have access to this whm control panel, so I assume we used this whm cpanel to host our websites.

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