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Which IP addresses should I add to the whitelist of my mail servers?


Which IP addresses should I add to the whitelist of my mail servers?



Unfortunately the servers that are handling mail of our customers switch IP too often to keep track of them.

To only accept messages from the SpamExpert filtering nodes you need to allow emails based on hostname "". This hostname contains all active delivery IP addresses. Alternatively you can allow traffic from any IP address with the PTR record *

Please make sure your firewall does not block port 53 TCP.

Alternatively if allowing emails based on hostname is not an option, you could change your destination mail server to receive on an alternative port, such as port 2525 instead of the default 25 . The special port can be set for delivery when editing the destination route for your domain.


If you still want to add the Spamexperts IPs, you can add the IPs shown in the following Link .



For users of our the old bundled configuration it is possible to use the information below.

To make sure you don't filter anything coming from our platform (since it is already filtered anyway) you can whitelist our platform in your own spam filters. You can also configure your mailserver to accept only incoming mail connections from this range IP addresses.

Here are all the IP addresses of our SpamExperts environment.

IPv4 IPv6 2a00:f10:10a:e::25:587:2 2a00:f10:10a:e::25:587:5

2a00:f10:10a:e::25:587:10 2a00:f10:121:400:42c:78ff:fe00:42e/64  
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