dhclient gives wrong IP addr when leases file exists

[Matthias Apitz]

When I go from my home network's AP (192.168.178.1) where I have as IP
addr 192.168.178.24 to the 'road' and use as AP my mobile it 
associates fine to the AP of my phone, but does not get
a correct IP addr from it via DHCP:

# ifconfig wlan0
wlan0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	ether 90:48:9a:92:9e:43
	inet 0.0.0.0 netmask 0xff000000 broadcast 255.255.255.255 
        ^^^^^^^^^^^^
	groups: wlan 
	ssid "Matthiass iPhone" channel 1 (2412 MHz 11g ht/20) bssid c6:0c:f7:42:62:81
	regdomain 108 indoor ecm authmode WPA2/802.11i privacy ON
	deftxkey UNDEF AES-CCM 2:128-bit txpower 20 bmiss 7 scanvalid 60
	protmode CTS ampdulimit 64k ampdudensity 4 shortgi wme burst
	roaming MANUAL
	media: IEEE 802.11 Wireless Ethernet MCS mode 11ng
	status: associated
	nd6 options=2b<PERFORMNUD,ACCEPT_RTADV,IFDISABLED,AUTO_LINKLOCAL>

I kill the dhclient alwaya and launch it by hand to see the problem: why it
is bound to the wrong IP addr (of my AP at home):

# killall dhclient
# dhclient wlan0
DHCPREQUEST on wlan0 to 255.255.255.255 port 67
DHCPACK from 172.20.10.1
bound to 192.168.178.24 -- renewal in 42768 seconds.
^^^^^^^^^^^^^^^^^^^^^^^^^ ?????

# ifconfig wlan0
wlan0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	ether 90:48:9a:92:9e:43
	inet 0.0.0.0 netmask 0xff000000 broadcast 255.255.255.255 
        ^^^^^^^^^^^^
	groups: wlan 
	ssid "Matthiass iPhone" channel 1 (2412 MHz 11g ht/20) bssid c6:0c:f7:42:62:81
	regdomain 108 indoor ecm authmode WPA2/802.11i privacy ON
	deftxkey UNDEF AES-CCM 2:128-bit txpower 20 bmiss 7 scanvalid 60
	protmode CTS ampdulimit 64k ampdudensity 4 shortgi wme burst
	roaming MANUAL
	media: IEEE 802.11 Wireless Ethernet MCS mode 11ng
	status: associated
	nd6 options=2b<PERFORMNUD,ACCEPT_RTADV,IFDISABLED,AUTO_LINKLOCAL>

When I move the file about the leases away, it works fine:

# killall dhclient
# mv /var/db/dhclient.leases.wlan0 /var/db/dhclient.leases.wlan0.away
# dhclient wlan0
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 6
DHCPOFFER from 172.20.10.1
DHCPREQUEST on wlan0 to 255.255.255.255 port 67
DHCPACK from 172.20.10.1
bound to 172.20.10.2 -- renewal in 42768 seconds.


# ifconfig wlan0
wlan0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	ether 90:48:9a:92:9e:43
	inet 172.20.10.2 netmask 0xfffffff0 broadcast 172.20.10.15 
        ^^^^^^^^^^^^^^^^
	groups: wlan 
	ssid "Matthiass iPhone" channel 1 (2412 MHz 11g ht/20) bssid c6:0c:f7:42:62:81
	regdomain 108 indoor ecm authmode WPA2/802.11i privacy ON
	deftxkey UNDEF AES-CCM 2:128-bit txpower 20 bmiss 7 scanvalid 60
	protmode CTS ampdulimit 64k ampdudensity 4 shortgi wme burst
	roaming MANUAL
	media: IEEE 802.11 Wireless Ethernet MCS mode 11ng
	status: associated
	nd6 options=2b<PERFORMNUD,ACCEPT_RTADV,IFDISABLED,AUTO_LINKLOCAL>

Any ideas?

	matthias
-- 
Matthias Apitz, ✉ guru at unixarea.de, http://www.unixarea.de/ +49-176-38902045
Public GnuPG key: http://www.unixarea.de/key.pub

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