When cnPilot APs are used to serve up a captive-portal network, the authentication status of the wireless clients is synchronised among those access points. This synchronisation is important because this is how clients that authenticate on one AP can seamlessly roam to a second one. The second AP knows the client has already gone through the authentication process, and will not redirect the client to a login page again.
While this synchronisation is seamless and automatic, it has a couple of limitations:
- Each AP can track the state of up to 1000 clients on their own
- The APs need connectivity with each other to be able to synchronise this status.
For larger networks with more clients (>1000, so say 10,000 total clients, or 100,000 total clients all across the network) this synchronisation can be coordinated by cnMaestro. In this mode APs will update cnMaestro with the state of the client, and new APs will also look up state on cnMaestro. So any number of clients can now roam between any number of Access Points, and all the client state is kept up to date on the wireless controller in cnMaestro.
In addition to scaling up the number of supported roaming clients, this also makes the client state resilient to Access Point restarts or losing connectivity to each other.
How to fix:
To enable this feature, tick the 'cnMaestro Managed Roaming' checkbox in Wireless LAN settings, in cnMaestro version 1.6.0 or later: