Observable behaviour
Client WiFi devices cannot obtain their IP addresses when connecting to a FreeBSD-13.0 server acting as an access point (hostap).Client devices run Win8.1 and various Androids, but the exact client software seems irrelevant to the problem.
Suspected technical reason
Local DHCP daemon, dhcpd, fails to start properly during reboot with WiFi interface in hostap mode.Details
I have a FreeBSD-13.0 server with two Ethernet interfaces (em0, igb0) and one WiFi interface (QCNFA222 card as ath0 -> wlan0). I have configured it as a wireless access point. It runs, among other things, a DHCP server for its wired and wireless clients. DHCP server seems to work just fine when started manually like shown below, with a few seconds interval between commands:# service hostapd start# service dhcpd startHowever,
dhcpd fails to listen on wlan0 interface if I run these very same commands quickly. It also fails to listen on wlan0 during system automatic boot or reboot.Reading /var/log/all.log suggested that it could be due to
wlan0 interface being temporarily down at the time when dhcpd is started. I've experimented a bit and found out that hostapd, when started, does indeed put wlan0 interface down and brings it back up much much later, sometimes after as long as 5 seconds. No wonder dhcpd can't bind to it...My Questions
- Is my guess correct? Is
hostapdbringing the interface down really the root cause of the problem? - What am I doing wrong? What should I do to make sure that
wlan0interface is up when startup scripts are starting DHCP daemon?
Files
Here are relevant (to my best judgement) excertps from logs and configs. My comments are preceeded with#, skipped lines are replaced with [...], exact IP addresses are redacted. Immediate cause of the problem is marked red./etc/rc.conf
Code:
ifconfig_em0="DHCP"
ifconfig_igb0="inet Y.Y.Y.Y netmask 255.255.255.0"
wlans_ath0="wlan0"
create_args_wlan0="wlanmode hostap country RU regdomain NONE mode 11g channel any mediaopt hostap -pureg -apbridge"
ifconfig_wlan0="HOSTAP inet X.X.X.X netmask 255.255.255.0"/etc/hostapd.conf
Code:
interface=wlan0
debug=1
ctrl_interface=/var/run/hostapd
ctrl_interface_group=wheel
ssid=ZZZZ
country_code=RU
wpa=2
wpa_psk_file=/etc/hostapd.wpa_psk
wpa_key_mgmt=WPA-PSK
wpa_pairwise=CCMP/var/log/all.log
Rich (BB code):
# em0 is the upstream link configured by DHCP client.
kernel: Starting dhclient.
kernel: em0: no link ...
[...]
kernel: em0: link state changed to UP
kernel: got link
kernel: DHCPREQUEST on em0 to 255.255.255.255 port 67
kernel: igb0: link state changed to UP
kernel: DHCPREQUEST on em0 to 255.255.255.255 port 67
kernel: DHCPACK from S.S.S.S
kernel: bound to Z.Z.Z.Z -- renewal in 1800 seconds.
# Proceed to initialize other interfaces
kernel: Starting Network: lo0 igb0 em0 wlan0.
[...]
kernel: wlan0: flags=8c43<UP,BROADCAST,RUNNING,OACTIVE,SIMPLEX,MULTICAST> metric 0 mtu 1500
kernel: ether MM:MM:MM:MM:MM:MM
kernel: inet X.X.X.X netmask 0xffffff00 broadcast X.X.X.255
kernel: groups: wlan
kernel: ssid "" channel 5 (2432 MHz 11g)
kernel: regdomain NONE country RU indoor ecm authmode OPEN privacy OFF
kernel: txpower 30 scanvalid 60 protmode CTS wme burst -apbridge dtimperiod 1
kernel: -dfs bintval 0
kernel: parent interface: ath0
kernel: media: IEEE 802.11 Wireless Ethernet autoselect mode 11g <hostap>
kernel: status: no carrier
kernel: nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
# Then hostapd is started.
kernel: Starting hostapd.
kernel: Configuration file: /etc/hostapd.conf
kernel: wlan0: interface state UNINITIALIZED->COUNTRY_UPDATE
[...]
# And finally DHCPD starts and fails.
# I suppose the error message is a bit misleading since wlan0 does have an IP address statically assigned right from its creation.
kernel: Starting dhcpd.
kernel: Can't listen on wlan0 - it has no IP address.
kernel: Listening on igb0 (Y.Y.Y.Y).