i'm having problems connecting over wireless. At the moment, I'm using wicd. It seems to get stuck on "Verifying AP association...". Without wicd I can get the connection up and ping the Net - but if I take eth0 down (ifconfig eth0 down), my wireless goes away too (same result if I unplug the wire instead). wicd is the only way I can bring eth0 back (which is the main reason I'm using it) - ifconfig eth0 and/or ifup eth0 do not re-enable the connection (I just discovered it leaves out the gateway. Adding the gateway back in re-enables the connection including wifi; I didn't want to delete the info about wicd above in case it gives someone an idea.)

Doing it manually, despite the errors (which it would be nice to also resolve) - allows me to ping the outside world:

ifup wlan0

ioctl[SIOCSIWENCODEEXT]: Invalid argument
ioctl[SIOCSIWENCODEEXT]: Invalid argument
ssh stop/waiting
ssh start/running, process 17336

ping -I wlan0 -c 4 8.8.8.8

PING 8.8.8.8 (8.8.8.8) from 192.168.0.12 wlan0: 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_req=1 ttl=43 time=48.8 ms
64 bytes from 8.8.8.8: icmp_req=2 ttl=43 time=47.9 ms
64 bytes from 8.8.8.8: icmp_req=3 ttl=43 time=48.7 ms
64 bytes from 8.8.8.8: icmp_req=4 ttl=43 time=53.2 ms

--- 8.8.8.8 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3003ms
rtt min/avg/max/mdev = 47.975/49.711/53.235/2.063 ms

# iwconfig

lo        no wireless extensions.

wlan0     IEEE 802.11bgn  ESSID:"TPLINK"  
      Mode:Managed  Frequency:2.427 GHz  Access Point: 64:66:xx:xx:xx:22   
      Bit Rate=108 Mb/s   Tx-Power=27 dBm   
      Retry  long limit:7   RTS thr:off   Fragment thr:off
      Encryption key:off
      Power Management:off
      Link Quality=70/70  Signal level=-39 dBm  
      Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
      Tx excessive retries:0  Invalid misc:3   Missed beacon:0
 bus info: pci@0000:03:00.0
   logical name: wlan0
   version: 01
   serial: f0:7d:68:c1:b4:13
   width: 64 bits
   clock: 33MHz
   capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical wireless
   configuration: broadcast=yes driver=ath9k driverversion=3.2.0-67-generic-pae firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11bgn
   resources: irq:17 memory:dfbf0000-dfbfffff

ip route

default via 192.168.0.1 dev eth0 
default via 192.168.0.1 dev wlan0  metric 100 
169.254.0.0/16 dev wlan0  scope link  metric 1000 
192.168.0.0/24 dev eth0  proto kernel  scope link  src 192.168.0.102 
192.168.0.0/24 dev wlan0  proto kernel  scope link  src 192.168.0.12

(For the record, I have no idea what the 169.254.0.0 address is doing there.)

uname -a

3.2.0-67-generic-pae #101-Ubuntu SMP Tue Jul 15 18:04:54 UTC 2014 i686 i686 i386 GNU/Linux

lshw -C network

  *-network               
   description: Ethernet interface
   product: NetXtreme BCM5751 Gigabit Ethernet PCI Express
   vendor: Broadcom Corporation
   physical id: 0
   bus info: pci@0000:02:00.0
   logical name: eth0
   version: 01
   serial: 00:11:11:59:fc:09
   size: 100Mbit/s
   capacity: 1Gbit/s
   width: 64 bits
   clock: 33MHz
   capabilities: pm vpd msi pciexpress bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
   configuration: autonegotiation=on broadcast=yes driver=tg3 driverversion=3.121 duplex=full firmware=5751-v3.23a ip=192.168.0.102 latency=0 link=yes multicast=yes port=twisted pair speed=100Mbit/s
   resources: irq:16 memory:dfcf0000-dfcfffff
  *-network
   description: Wireless interface
   product: AR5418 Wireless Network Adapter [AR5008E 802.11(a)bgn] (PCI-Express)
   vendor: Qualcomm Atheros
   physical id: 0

/etc/network/interfaces

# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback

source /etc/network/interfaces.eth0
source /etc/network/interfaces.wlan0

/etc/network/interfaces.eth0

#Main Interface
auto eth0
iface eth0 inet static
address 192.168.0.102
netmask 255.255.255.0
gateway 192.168.0.1

/etc/network/interfaces.wlan0

auto wlan0 
iface wlan0 inet static
address 192.168.0.12
gateway 192.168.0.1
dns-nameservers 192.168.0.1 8.8.8.8
netmask 255.255.255.0
wpa-driver wext
wpa-ssid TPLINK
wpa-ap-scan 1
wpa-proto RSN
wpa-pairwise CCMP
wpa-group CCMP
wpa-key-mgmt WPA-PSK
wpa-psk dca1badb5fd4e9axxx4xxdaaxxfa91xx610bxx6a7d57ef67af9809dxx6af42e39

/etc/wpa_supplicant.conf

    ctrl_interface=/var/run/wpa_supplicant

network={
    ssid="TPLINK"
    psk="my password"
    key_mgmt=WPA-PSK
    proto=RSN
    pairwise=CCMP
    group=CCMP
}

ifdown eth0

ifdown: interface eth0 not configured

ifconfig

eth0      Link encap:Ethernet  HWaddr 00:11:xx:xx:xx:09  
          inet addr:192.168.0.102  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::211:11ff:fe59:fc09/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:213690 errors:0 dropped:0 overruns:0 frame:0
          TX packets:155266 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:220057808 (220.0 MB)  TX bytes:21137696 (21.1 MB)
          Interrupt:16 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:196412 errors:0 dropped:0 overruns:0 frame:0
          TX packets:196412 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:153270697 (153.2 MB)  TX bytes:153270697 (153.2 MB)

wlan0     Link encap:Ethernet  HWaddr f0:7d:xx:xx:xx:13  
          inet addr:192.168.0.12  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::f27d:68ff:fec1:b413/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:11335 errors:0 dropped:0 overruns:0 frame:0
          TX packets:7287 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:2563290 (2.5 MB)  TX bytes:855746 (855.7 KB)

ifconfig eth0 down

ifconfig

eth0      Link encap:Ethernet  HWaddr 00:xx:xx:xx:xx:09  
          inet addr:192.168.0.102  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::211:11ff:fe59:fc09/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:2 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:192 (192.0 B)  TX bytes:94 (94.0 B)
          Interrupt:16 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:196418 errors:0 dropped:0 overruns:0 frame:0
          TX packets:196418 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:153270871 (153.2 MB)  TX bytes:153270871 (153.2 MB)

wlan0     Link encap:Ethernet  HWaddr f0:7d:xx:xx:xx:13  
          inet addr:192.168.0.12  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::f27d:68ff:fec1:b413/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:11359 errors:0 dropped:0 overruns:0 frame:0
          TX packets:7293 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:2565482 (2.5 MB)  TX bytes:856363 (856.3 KB)

ip route

default via 192.168.0.1 dev wlan0  metric 100 
169.254.0.0/16 dev wlan0  scope link  metric 1000 
192.168.0.0/24 dev wlan0  proto kernel  scope link  src 192.168.0.12 
192.168.0.0/24 dev eth0  proto kernel  scope link  src 192.168.0.102 

ping -I wlan0 -c 4 8.8.8.8

PING 8.8.8.8 (8.8.8.8) from 192.168.0.12 wlan0: 56(84) bytes of data.

--- 8.8.8.8 ping statistics ---
4 packets transmitted, 0 received, 100% packet loss, time 3024ms

ping -I eth0 -c 3 router

PING router (192.168.0.1) from 192.168.0.102 eth0: 56(84) bytes of data.

--- router ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2015ms

ping -I wlan0 -c 3 router

PING router (192.168.0.1) from 192.168.0.12 wlan0: 56(84) bytes of data.

--- router ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2014ms

Let me know if you need more info.

Thank you in advance.