We don't recommend that you install extended device discovery on notebook computers, since they may connect to other networks that you don't want to monitor, such as hotel or airport networks. To help prevent discovery of devices that aren't on your network, the core server ignores IP addresses where the first and second IP address octets are plus or minus 10 from that of the core server. For example, if your core server's IP address is 192.168.20.17, extended device discovery on the core server will ignore addresses above 188.8.131.52 and addresses below 184.108.40.206.
You can disable this feature by adding the following DWORD registry key to the core server and setting its value to 0:
You can set the Filter value to 1 to enable filtering again.
You can adjust the first and second octet monitoring ranges by adding the following DWORD registry keys to the core server and setting their values to the numeric range that you want monitored (the default is 10 for the first and second octets):
FilterThreshold1 contains the range for the first octet and FilterThreshold2 contains the range for the second octet.