Hi owen,
Probably your computer on a switched network,
S1. install nexeye switchsnarf
http://www.nexeye.com/switchsnarf to your computer, Then run nexeye monitoring again,
S2. re-configure your network for sniffing,
---from nexeye setup manual ---
nexeye is an application that catches and analyse the network packages and transforms the data into certain files types. Accordingly certain adjustments need to applied to the network that enables nexeye to catch the packages. Below is provided the options for the network setup:
1. Network over the Hub
Network sharing can be established by using a Hub.
A network package received by one of the ports of the Hub is copied to teh other ports. Accordingly all packages in the network can be seen by the other users in the network.
In a shared environment established with a Hub, nexeye can be installed in any PC connected to any of the ports of the Hub.
2. Switch Networks
Switches are the most common used network equipment. A switch operates on the Data _link_ _layer_ where the switch identifies the physical (MAC) addresses of the PCs that is connected to the port of the switch. The address is then recorded on the ARP table of the switch. When a package is received by the switch, the MAC address of the package is first identified and then routed to the port that is recorded in the ARP.
Managed Switch: If you are using a managed switch nexeye can be installed on a PC connected to the analysis port of the switch (span, monitor). By assigning and configuring the port on your switch for analysis, you can start monitoring your network with nexeye through this port.
3. Hub between the switch and router
If your switch is not a manageable switch, you can monitor your network by connecting a Hub between the switch and the router. nexeye shall be installed and operated on a PC connected to any of the port of the Hub.
4. Gateway PC Installation
Nexeye can be installed and operated on a gateway PC connected between the switch and the router. The PC should have NAT capability and be installed with two network cards