Practical Examples
The IP filters you create work together to provide security for your network. The examples that follow show how to use filters to achieve some specific goals.
Block Access to Internet Users
This section shows you, as an example, how to allow users on your subnet access to your server’s Web service, but deny access to the general public on the Internet:
To do this:
1In Server Admin, choose Firewall from the Computers & Services list.
2Click Settings.
3Select the General tab.
4Select the Any address group.
5Make sure that Web Service is disabled in the right pane.
6Click the Add button to create an address range.
7Name the address group.
8Add the local network address range.
This is done by using an example address from the network with its network mask in CIDR notation. For example, if a user has an address of 192.168.1.20 and the network mask is 255.255.255.0, then enter 192.168.1.20/24.
9Click OK.
10Select your newly created address group.
11Select “Web Service” in the right pane to enable web access.
12Click Save.
Block Junk Mail
This section shows you, as an example, how to reject email from a junk mail sender with an IP address of 17.128.100.0 and accept all other Internet email:
Chapter 3 IP Firewall Service
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