The devices page shows you the status of all the devices on your network with regards to if they have communicated with Smoothwall Monitor recently or not. This is so that you can know if Monitor is working on a device or not and know which machines that might need attention. If not, it might be that the device just hasn't been used but mostly it indicates that there might be something wrong with the device connecting to Monitor.
You can view a list of all the devices running Monitor and their status, to see when they were last connected, when they last sent data and if they require an update.
You can sort the view by the column headers and search by device name or serial.
If the clients aren't showing, it's because the clients not being able to contact portal.smoothwall.com or monitor.smoothwall.com from their net connection. Please ensure that you whitelist an authentication exception for the two URLs and then connect a machine with the client installed, it should sense the network change and then attempt a dial home again.
If a device hasn't connected to Monitor for several days, this might be because of changes to your network. For example, you might have wiped a device and not reinstalled the client or a new filter or firewall might block the communication to the Monitor end points, where Monitor sends its messages. You can see the end points here: https://vclient-api.smoothwall.com. Ensure that you have added these to your firewall or filter as an exception.