display a list of the physical interfaces. The first few lines of the interface list for the SG4500 Series
are shown below.
Click on the interface in the list which is to be connected to the Internet. The properties for this
interface will now appear and the relevant settings can be entered or changed.
Press OK to save the changes. Although changes are remembered by CorePlus, the changed
configuration is not yet activated and won't be activated until CorePlus is told to activate the
changed configuration.
Remember that DHCP should not be enabled when using static IP addresses and also that the IP
address of the
Default Gateway
(which is the ISP's router) must be specified. As explained in more
detail later, specifying the
Default Gateway
also has the additional effect of automatically adding
a route for the gateway in the CorePlus routing table.
At this point, the connection to the Internet is configured but no traffic can flow to or from the
Internet since all traffic needs a minimum of the following two CorePlus configuration objects to
exist before it can flow through the Clavister Security Gateway:
•
An
IP rule
defined in a CorePlus
IP rule set
that explicitly allows traffic to flow from a given
source network and source interface to a given destination network and destination
interface.
•
A
route
defined in a CorePlus routing table which specifies on which interface CorePlus can
find the traffic's destination IP address.
If multiple matching routes are found, CorePlus uses the route that has the smallest (in other
words, the narrowest) IP range.
We must therefore first define an IP rule that will allow through traffic from a designated source
interface and source network. In this case let us assume we want to allow web browsing from the
internal network
ge3_net
connected to the interface
ge3
to be able to access the public Internet.
To do this, we first go to Rules > IP Rule Sets > main in the navigation tree.
The empty
main
IP rule set will now appear. Press the Add button at the top left and select IP
Rule from the menu.
The properties for the new IP rule will appear. In this example, we will call the rule
lan_to_wan
.
Chapter 3: CorePlus Configuration
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