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Router's Hides the Actual IP Address

When you run any server, HTTP, POP3, IMAP or SMTP, Xeams gets the IP addresses of the connecting client from TCP/IP headers. Consider the image below:

In this above example, two different clients are connecting from the Internet. One is using an IMAP (185.45.45.6) and second is another SMTP server (158.19.46.84) trying to send an email. Although both of these clients are coming in from the Internet and have different IP addresses, you see 192.168.1.1, which is your router's IP address in every log, giving you an impression that your router is actually sending these messages. In some cases you may see the WAN IP address of your router instead of 192.168.1.1.

Why does this happen

This happens because your router is masquerading the actual client's IP address and is acting sort of like a reverse proxy. To prevent this, refer to your router's documentation to see how to disable this feature. For example, click here to see how to prevent this if you're using a firewall from Fortinet.

Disadvantages of such configuration

There are several disadvantages if your router hides the actual IP address:

• Xeams will think every incoming email is coming from your router, which negatively affects spam filtering. In fact, you will lose about 60% of spam filtering capabilities in Xeams if this problem is not fixed.
• You will end up getting your router's IP address blacklisted if someone on the Internet is trying to misbehave. For example, if someone tries to perform a dictionary attack, Xeams will think your router is doing that.
• Troubleshooting problems becomes difficult because logs will only contain your router's IP address

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