Home / server / Questions / 226046
Accepted
LanceBaynes
Asked: 2011-01-24 23:19:00 +0800 CST

how to get a list of the connected wifi clients in OpenWrt 10.03?

  • 772

how to get a list of the connected wifi clients in OpenWrt 10.03?

linux openwrt

5 Answers

  1. In order to see associated wifi clients, even if they don't have a DHCP Client or have no ip, you have to ask the AP for associated wifi devices:

    # MAC80211
iw dev wlan0 station dump

# Universal (Tested with OpenWRT 14.07 and 15.05.X)
# iwinfo must be installed first as it is optional
# opkg update && opkg install iwinfo
iwinfo wlan0/wl0/ath0 assoclist

# using hostapd
ubus call hostapd.wlan0 get_clients

# Proprietary Broadcom (wl)
wl -i wl0 assoclist
 
# Proprietary Atheros (madwifi)
wlanconfig ath0 list sta

    This way you will also see the connection speed. For me this is looking like this:

    # iwinfo wlan0 assoclist
12:34:56:78:9A:BC  -26 dBm / -95 dBm (SNR 69)  1930 ms ago
RX: 24.0 MBit/s, MCS 0, 20MHz                   3359 Pkts.
TX: 130.0 MBit/s, MCS 14, 20MHz, short GI       1209 Pkts.
    • 18
  2. Best Answer

    You may use the arp-table, or DHCP-leases. Not a perfect solution, maybe it's enough?

    List arp-table

    arp

    List DHCP-leases

    cat /tmp/dhcp.leases

    ... and combined

    for ip in $(arp | grep -v IP | awk '{print $1}'); do 
    grep $ip /tmp/dhcp.leases; 
done
    • 16

  3. Instead of cat /tmp/dhcp.leases|wc -l and arp -a, my solution is 

    opkg update
opkg install arp-scan
arp-scan --interface=br-lan --localnet | grep responded | awk '{print $12}'

    It will return the number of devices which connected to OpenWRT by LAN port. Almost real time.

    • 2

  4. How about nmap?

    opkg install nmap

    Then do a stealth scan of your subnet (likely 192.168.1.0/24)

    nmap -sS 192.168.1.0/24

    This will list services running on the clients as well. It may also set off alarms if the client has port-scan detecting software (i.e snort) installed so be careful.

    • 1

  5. To get them directly from hostapd (the daemon that manages the access point):

    $ ubus call hostapd.wlan0 get_clients

{
    "freq": 2462,
    "clients": {
        "<mac addr 1>": {
            "auth": true,
            "assoc": true,
            "authorized": true,
            "preauth": false,
            "wds": false,
            "wmm": true,
            "ht": true,
            "vht": false,
            "wps": false,
            "mfp": false,
            "rrm": [
                0,
                0,
                0,
                0,
                0
            ],
            "aid": 1
        }
    }
}

    (or replace wlan0 with the interface you are interested in)

    • 1