How to exclude a certain IP/IP range from reverse DNS checks
Solution
In a setup were the AXIGEN Mail Server is configured with the Reject message if the originating IP has no reverse DNS entry option as an antispam method, excluding an IP/IP range from the reject action can be configured via WebAdmin->Security & Filtering context-> Advanced Settings section, by adding a new Acceptance / Routing rule.
From this new section you should:
Define a suggestive name for this rule for ease of tracking the action enforced.
In the Conditions area you should make sure that this rule is applied For incoming messages that match ALL of the conditions
Next, you should add the following two conditions:
Remote address->IP add this rule and configure it to match the address/address range. This condition can be configured by defining the IP address as single IP/ IP range/ CIDR/ Netmask format
DNS checks->Reverse DNS, this condition should be configured with Fail as the result.
From the Actions section add the following entry:
SMTP->action and set this to Accept
Please note that the Explanation section is optional for this setting.
By saving the new configuration details of this SMTP Acceptance and Routing rule, e-mails received from the defined IP/IP range will be accepted even if the reverse DNS checks fail.
From this new section you should:
Define a suggestive name for this rule for ease of tracking the action enforced.
In the Conditions area you should make sure that this rule is applied For incoming messages that match ALL of the conditions
Next, you should add the following two conditions:
Remote address->IP add this rule and configure it to match the address/address range. This condition can be configured by defining the IP address as single IP/ IP range/ CIDR/ Netmask format
DNS checks->Reverse DNS, this condition should be configured with Fail as the result.
From the Actions section add the following entry:
SMTP->action and set this to Accept
Please note that the Explanation section is optional for this setting.
By saving the new configuration details of this SMTP Acceptance and Routing rule, e-mails received from the defined IP/IP range will be accepted even if the reverse DNS checks fail.
OS:
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