1.
Ensure the Policy tab is selected within Firestarter and rightclick beneath the Deny Service (or Allow Service) heading near the bottom of the program window. In the menu that appears, select Add Rule.
2.
As when creating rules, select the type of connection you’d like to allow/deny from the Name dropdown list. Ignore the sections beneath the When The Source Is heading—they are only for use if Firestarter is managing Internet connection sharing on your computer.
3.
To create a custom rule for a particular port number, manually type a name of your own choosing into the Name field (although this is a dropdown list you can still type within it), and type the port number into the Port box.
TIP If you’ve opted for a whitelist (restrictive) policy, at the very least you should create individual rules for HTTP, HTTPS, POP3, and SMTP. For a complete list of popular TCP/IP ports, that you can use to create additional rules, see http://en.wikipedia.org/wiki/Port_number. 4.
When done, click the ADD button, and the APPLY POLICY button on the main toolbar. Then close Firestarter.
The new rule takes effect immediately. To delete a rule at a later stage, right-click it and select Remove Rule. Then click APPLY POLICY.
Turning off diagnostic tool responses
There’s an additional step you can take to protect your computer from potential Internet threats: turning off responses to diagnostic tools. However, this will mean you won’t be able to “ping” your computer. This can be useful when diagnosing network problems. To turn off diagnostic tool responses, click Edit Preferences in Firestarter’s main program window, select ICMP Filtering from the list on the left of the dialog box that appears, and put a check in Enable ICMP Filtering. Don’t put a check in any of the boxes beneath this! Once done, click the ACCEPT button, then click the APPLY POLICY button in the main toolbar, and close the Firestarter program.
Installing antivirus
Many people say using an antivirus program with Ubuntu is not necessary. It’s hard to argue. There are practically no viruses or
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