We currently use /webacs/api/v1/data/Clients to match an IP address to a MAC address so our in-house web BYOD portal knows the mac address of incoming clients allowing us to do things like:
Display device specific posture information
Autocomplete the mac address for new device registrations
However I notice the client data is not live and appears to be polled every 15 minutes.
How safe would it be to poll client data more frequently (for example every minute, 30 seconds etc) so we have live data? or are their better places to look for live IP to MAC address data for wireless clients?
Brunel University London
Increasing the frequency of the polling will increase resource consumption on both the device and the PI appliance, as well as increase storage usage on PI. We (Cisco) can't really give you a recommended polling period (other than the default) because the impact depends on the specifics of your network and the hardware that the appliance is running on.
You can try checking how long it takes the job to run, and increase the frequency based on that (for example, if it takes 4 minutes to collect client data, then every minute or every 30 seconds would be much too frequent).
I'm not an expert on web portals, but to answer your question about alternate ways of getting live IP/MAC data is to set up SNMP traps on your WLCs for client assoc/deassoc events and send these traps to your web portals. Your wireless controllers will send these traps in real time and they include both the MAC address and IP address (if client is DHCP) in the same trap.
This is how our NAC system gets real-time client information from our network devices, for instance.