12.04, cannot detect wireless network after router reset

[vghaisas]

I have an IdeaPad S10e running Ubuntu 12.04 for the past 6 months or so and was using the wireless network without any problems.

Recently, somebody accidentally switched off the Linksys EA4500 router. After it was turned on again, my Windows 7 computer had no problems reconnecting but the Ubuntu 12.04 system does not detect any available wireless network at all.

Can anybody offer any specific solutions?

Thanks in advance.

[vghaisas]

If they help, further details are as follows.

The output of lshw -c network:

sudo lshw -c network
  *-network               
       description: Ethernet interface
       product: NetLink BCM5906M Fast Ethernet PCI Express
       vendor: Broadcom Corporation
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: eth0
       version: 02
       serial: 00:23:8b:bf:2f:40
       capacity: 100Mbit/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm vpd msi pciexpress bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=tg3 driverversion=3.121 firmware=sb v3.04 latency=0 link=no multicast=yes port=twisted pair
       resources: irq:44 memory:f0200000-f020ffff
  *-network
       description: Wireless interface
       product: BCM4312 802.11b/g LP-PHY
       vendor: Broadcom Corporation
       physical id: 0
       bus info: pci@0000:05:00.0
       logical name: eth1
       version: 01
       serial: 00:24:2c:e6:28:d9
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=wl0 driverversion=6.20.155.1 (r326264) latency=0 multicast=yes wireless=IEEE 802.11abg
       resources: irq:18 memory:f0400000-f0403fff

Of ifconfig:

ifconfig
eth0      Link encap:Ethernet  HWaddr 00:23:8b:bf:2f:40  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:16 

eth1      Link encap:Ethernet  HWaddr 00:24:2c:e6:28:d9  
          inet6 addr: fe80::224:2cff:fee6:28d9/64 Scope:Link
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:25 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:18 

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:4388 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4388 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:348736 (348.7 KB)  TX bytes:348736 (348.7 KB)

And of lspci:

lspci
00:00.0 Host bridge: Intel Corporation Mobile 945GSE Express Memory Controller Hub (rev 03)
00:02.0 VGA compatible controller: Intel Corporation Mobile 945GSE Express Integrated Graphics Controller (rev 03)
00:02.1 Display controller: Intel Corporation Mobile 945GM/GMS/GME, 943/940GML Express Integrated Graphics Controller (rev 03)
00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 02)
00:1c.0 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 1 (rev 02)
00:1c.1 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 2 (rev 02)
00:1c.2 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 3 (rev 02)
00:1d.0 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #1 (rev 02)
00:1d.1 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #2 (rev 02)
00:1d.2 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #3 (rev 02)
00:1d.3 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #4 (rev 02)
00:1d.7 USB controller: Intel Corporation N10/ICH 7 Family USB2 EHCI Controller (rev 02)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev e2)
00:1f.0 ISA bridge: Intel Corporation 82801GBM (ICH7-M) LPC Interface Bridge (rev 02)
00:1f.1 IDE interface: Intel Corporation 82801G (ICH7 Family) IDE Controller (rev 02)
00:1f.2 IDE interface: Intel Corporation 82801GBM/GHM (ICH7-M Family) SATA Controller [IDE mode] (rev 02)
00:1f.3 SMBus: Intel Corporation N10/ICH 7 Family SMBus Controller (rev 02)
02:00.0 Ethernet controller: Broadcom Corporation NetLink BCM5906M Fast Ethernet PCI Express (rev 02)
05:00.0 Network controller: Broadcom Corporation BCM4312 802.11b/g LP-PHY (rev 01)

[varunendra]

Hi,

I've edited the title for you.
As for the wireless issue, please follow the "Wireless Script" link in my signature, and post back its result.

Also, although may sound silly, have you tried resetting your router again? If not, try powering it off > wait for at least half a minute (even 4 if not a problem) > power it on > try connecting again.

A reboot can often do miracles.

If you can do so, run the wireless script afterwards.

[Noelofkraal]

Rebooting has always worked for me , both laptops and routers
try that and post results

[vghaisas]

Thanks for fixing the title.

And yes, I've tried rebooting both, the router and the laptop. Didn't change anything. I shall try again in a couple of hours to check again.

Am I correct in assuming that the Wireless Script generates a detailed diagnostic report?

[varunendra]

Thanks for fixing the title.

No problem, part of the job

Am I correct in assuming that the Wireless Script generates a detailed diagnostic report?

Yes.
It gives us 'almost' everything needed to troubleshoot most of the wifi issues. Its result (netinfo.txt) is a simple text file which you can check yourself before posting here.

[vghaisas]

Ok, sorry for abandoning my own question. Pesky exams...

The good news is that internet's suddenly working again. For no apparent reason... As always.

Thanks for all your help guys!