Guests with no IP?

  • Greetings,
    I am running an open wifi (AP connected via opt2, with pfsense running the dhcp server for wireless clients). More often than not the AP reports more active clients (via snmp) than there are active DHCP leases, suggesting that there are people connected without an IP.

    Like currently there is one active DHCP lease and me using the network. But the AP reports three connected devices. There are times where the numbers match, so there is no observation error.

    Why is that? I am sure there is a technical explaination that I am just lacking the knowledge to explain.
    Thank you.

  • Rebel Alliance Developer Netgate

    It could be people connecting with the wrong key. I know at times my laptop has reported that it was associated, even though I mistyped the key, but I'd get no network data since it was all dropped.

    If your AP can give more detailed logging (syslog, perhaps) you might be able to monitor that a bit closer and solve the mystery.

    If they just couldn't pull from DHCP, most things would still choose a link-local IP (169.254.x.x) which may be seen by the AP.

  • The network is passwordless. So no option 1.
    For the case where they can't get an IP via DHCP, their connection would be useless (at least for connecting to the internet), as I filter all non-LAN IP traffic. Still, the devices keep being connected for a long time suggesting they are not being used. But - automatically established connections would always try DHCP, right?

    Maybe some people just chose a static IP in the DHCP range?
    Haven't had a chance to look into the AP logs yet.

  • @senser:

    Maybe some people just chose a static IP in the DHCP range?

    Oh yeah!  ;D

  • Check ARP.

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