How to change your DNS servers

The DNS servers which O2 provide generally work well. However, if you would like to use alternative DNS servers to the ones O2 provide when using the O2 Wireless Box II/III (router), here are the instructions for achieving this.

One example of a third-party DNS provider is Google Public DNS.

Please note: You must use the router's built-in DHCP server for these instructions to work. If you set your computer's LAN IP address manually it will not work. See: Getting your computer's IP address via DHCP.

1) Open a Command Prompt and telnet to 192.168.1.254 (Windows Vista or Windows 7 users without telnet, see bottom of page).

2) Log in with Username: SuperUser. The password is either O2Br0ad64nd or the serial number of your router printed on its underside (excluding the bit in brackets).

3) Paste in the following lines changing primdns and secdns to whatever DNS servers you wish to use (use the little icon at the top-left of the command prompt window in order to paste). You do not need to edit the line starting with "dns client dnsadd". The example below sets your DNS to the Google Public DNS service. Use "none" for secdns if you don't have a secondary DNS server.

dns server config state=disabled
dhcp server config state=disabled
dhcp server lease flush
dhcp server pool config name=LAN_private primdns=8.8.8.8 secdns=8.8.4.4
dhcp server config state=enabled
dns client flush
dns client dnsadd addr=87.194.255.155
saveall
exit

4) Type "ipconfig /renew" or reboot your computer to pick up the new DNS servers.

Please note: If you have previously set up static IP addressing for any of your devices using steps 1 to 3 on Forwarding ports then you will need to set these up again.

To go back to using O2's DNS server, repeat the above steps but paste this into telnet during step 3):

dns server config state=enabled
dhcp server config state=disabled
dhcp server lease flush
dhcp server pool config name=LAN_private primdns=none secdns=none
dhcp server config state=enabled
dns client flush
dns client dnsadd addr=127.0.0.1
saveall
exit

Special note for Windows Vista and Windows 7 users: telnet is not installed by default. Go to:

Control Panel > Programs > Turn Windows features on or off

Put a tick in "Telnet Client" and click "OK"