Graybeard
Well-Known Member
What is a hostname?
Every legitimate internet ISP and WWW server using the Internet has a hostname!
Every email server MUST have a hostname and reverse DNS resolution to identify itself to other servers or the email SHOULD be rejected as Spam.
Check your IP with this tool and you should see your reverse DNS that advertised who you are.
IP address to hostname lookup (reverse DNS check)
Tools are for fools
Here is where it gets tricky: many IPs of servers are not real people will refuse a reverse lookup
2(SERVERFAIL) >>> Cloudfront is famous for this (ex: if your server is behind Cloudfront and trying to connect directly to my ad [click bot] or trying to scrape my website(s) content?
3(NXDOMAIN) is a common reply when the server is either not active or is in hiding
Unless you ban this ASN you will be bleeding
Just white list the servers that you have a business relationship with.
This one is more obvious
If you cannot detect this then you won't last long in the commercial internet
Proxy servers are the source of most internet frauds -- so is tor FYI
Every legitimate internet ISP and WWW server using the Internet has a hostname!
Every email server MUST have a hostname and reverse DNS resolution to identify itself to other servers or the email SHOULD be rejected as Spam.
Check your IP with this tool and you should see your reverse DNS that advertised who you are.
IP address to hostname lookup (reverse DNS check)
Tools are for fools
Here is where it gets tricky: many IPs of servers are not real people will refuse a reverse lookup
2(SERVERFAIL) >>> Cloudfront is famous for this (ex: if your server is behind Cloudfront and trying to connect directly to my ad [click bot] or trying to scrape my website(s) content?
3(NXDOMAIN) is a common reply when the server is either not active or is in hiding
Unless you ban this ASN you will be bleeding
Just white list the servers that you have a business relationship with.
This one is more obvious
If you cannot detect this then you won't last long in the commercial internet
Proxy servers are the source of most internet frauds -- so is tor FYI
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