- 1). Launch the terminal emulator utility on the computer. For example, if you are using Putty as a terminal emulator, double-click on the "Putty" icon on the computer's desktop.
- 2). Log in to the firewall as Administrator and enter privileged mode. The specific way of performing this step depends on the firewall's model. For example, for a Cisco 1841, type "en" and press "Enter" to enter privileged mode. Enter the administrator's password for the router. Type "configure terminal", then press "Enter."
- 3). Configure a new server for the Domain Name System. For example, on an 1841, type the following command:
IP name-server 8.8.4.4
Replace "8.8.4.4" with the IP address of the DNS server you want to use. Press "Enter." The firewall is reconfigured at that point.
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