How to Block an IP Address using IPSec

This article will walk you through how to block an individual IP address from accessing your server, using an IPSec Security Policy.
For various reasons, you may find yourself wanting to block a specific IP address from accessing your server.
Simply following these instructions showing how to create an IPSec Security Policy specifying to block access to a specific IP address.

Click on the Start Menu and Click on Run.


Type "secpol.msc" and Click OK.


When the Local Security Settings console opens, Click on "IP Security Policies on Local Computer".


Right Click in the Right Window Pane and Click "Create IP Security Policy".


Click Next when the Wizard opens.


Here you can name your new IPSec Security Policy. In this example, we named it "Blocked IPs". When you are ready, Click Next.


Click Next


Click Next


Click Yes


Click Finish


Uncheck the "Use Add Wizard" checkbox, then Click "Add...".


Click the "Add..." button.


Uncheck the "Use Add Wizard" checkbox, then Click "Add...".


Click the dropdown menu for "Source address" and choose "A specific IP Address".


Here is where you enter what IP address you want to Block. In this example, we are going to block "129.12.74.220".

Click the dropdown menu for "Destination address" and choose "My IP Address", then Click OK.


Click OK


Select the newly created Filter, and click on the "Filter Action" tab.


Select the "SI - Deny" Rule and Click Apply.


Click OK, then Apply and OK again to get back to the main console window.

Right Click on the newly created IPSec Security Policy, and select "Assign".


If successfull, it should state that the policy is assigned. Your server is now blocking all requests to that specific IP address.