Difference between revisions of "Wireless Tips"
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All too frequently, one will spend a whole bunch of time trying to configure a seemingly non-functional wireless only to realize later that there was a much simpler solution. First, look for a button or switch or combination of keys to activate/deactivate the wireless. For example, is there a button above the keyboard? a switch on the side? maybe Fn + F5 turns the wireless on and off? | All too frequently, one will spend a whole bunch of time trying to configure a seemingly non-functional wireless only to realize later that there was a much simpler solution. First, look for a button or switch or combination of keys to activate/deactivate the wireless. For example, is there a button above the keyboard? a switch on the side? maybe Fn + F5 turns the wireless on and off? | ||
| − | === | + | === lspci is your friend === |
| − | + | The '''lspci''' command is a utility for displaying information about all PCI buses in the system and all devices connected to them. It will tell you about your wireless card, if there is one installed. In particular, it will tell you whether your wireless card has a Broadcom chipset (which, if it does, you'll need to install some stuff - see below). | |
| − | + | EXAMPLE OF BROADCOM CHIPSET | |
| − | |||
=== ifconfig: am I connected? === | === ifconfig: am I connected? === | ||
The '''ifconfig''' command configures a wired network interface. It is a useful command for determining whether or not you're connected to a network AND which network interface is being used to connect (i.e. whether you're connected to a wireless or wired network). | The '''ifconfig''' command configures a wired network interface. It is a useful command for determining whether or not you're connected to a network AND which network interface is being used to connect (i.e. whether you're connected to a wireless or wired network). | ||
| − | + | eth0 Link encap:Ethernet HWaddr 08:00:46:0E:8C:D8 | |
inet addr:192.168.2.252 Bcast:192.168.2.255 Mask:255.255.255.0 | inet addr:192.168.2.252 Bcast:192.168.2.255 Mask:255.255.255.0 | ||
inet6 addr: fe80::a00:46ff:fe0e:8cd8/64 Scope:Link | inet6 addr: fe80::a00:46ff:fe0e:8cd8/64 Scope:Link | ||
| Line 22: | Line 21: | ||
RX bytes:1050713 (1.0 MiB) TX bytes:111359 (108.7 KiB) | RX bytes:1050713 (1.0 MiB) TX bytes:111359 (108.7 KiB) | ||
| − | This example shows that interface '' | + | This example shows that interface ''eth0'' is connected (because it shows an inet address). To determine whether ''eth0'' is the wired or wireless interface, use '''iwconfig''' |
=== iwconfig: no wires! === | === iwconfig: no wires! === | ||
The '''iwconfig''' command configures a wireless network interface. It is a useful command for determining which interface is being used for wireless networking. | The '''iwconfig''' command configures a wireless network interface. It is a useful command for determining which interface is being used for wireless networking. | ||
| − | + | ||
| + | eth0 no wireless extensions. | ||
| + | eth1 radio off ESSID:"" | ||
| + | Mode:Managed Channel:0 Access Point: Not-Associated | ||
| + | Bit Rate:0 kb/s Tx-Power=off Sensitivity=8/0 | ||
| + | Retry limit:7 RTS thr:off Fragment thr:off | ||
| + | Power Management:off | ||
| + | Link Quality:0 Signal level:0 Noise level:0 | ||
| + | Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 | ||
| + | Tx excessive retries:0 Invalid misc:0 Missed beacon:0 | ||
| + | |||
| + | The above example shows 3 important things: (1) that your wireless interface is ''eth1'', (2) that ''eth0'' is your wired network (because it reads "no wireless extension"), and (3) that your wireless is turned off ("radio off"). When you see "radio off" this generally means there's a physical button somewhere on the laptop that is currently in the off position. If you switched on the wireless and then ran '''iwconfig''' you might see something like this: | ||
| + | eth1 IEEE 802.11g ESSID:"freegeek" | ||
| + | Mode:Managed Frequency:2.422 GHz Access Point: 00:14:BF:2B:41:1D | ||
| + | Bit Rate:54 Mb/s Tx-Power=20 dBm Sensitivity=8/0 | ||
| + | Retry limit:7 RTS thr:off Fragment thr:off | ||
| + | Power Management:off | ||
| + | Link Quality=93/100 Signal level=-34 dBm Noise level=-89 dBm | ||
| + | Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 | ||
| + | Tx excessive retries:0 Invalid misc:0 Missed beacon:4 | ||
| + | Note that the ESSID is "freegeek." This means that you're connected to the Free Geek wireless network. | ||
=== dhclient === | === dhclient === | ||
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* If you just type '''dhclient''' it will try all interfaces (wireless and wired) | * If you just type '''dhclient''' it will try all interfaces (wireless and wired) | ||
* You can specify which interface you would like by typing '''dhclient [interface]''' | * You can specify which interface you would like by typing '''dhclient [interface]''' | ||
| − | : EXAMPLE: if you run '''iwconfig''' and discover that your wireless interface is '' | + | : EXAMPLE: if you run '''iwconfig''' and discover that your wireless interface is ''eth1'', then running '''dhclient eth1''' will only try to connect your laptop to any wireless network. If you specifically want to connect to the "freegeek" wireless network, you can type '''dhclient eth1 essid freegeek''' |
=== Broadcom chipset === | === Broadcom chipset === | ||
| Line 39: | Line 58: | ||
# System > Administration > Hardware Drivers | # System > Administration > Hardware Drivers | ||
#: If present, select "Broadcom B43 wireless driver" | #: If present, select "Broadcom B43 wireless driver" | ||
| − | # Manual installation. Open a terminal and type the following command to install b43-fwcutter and fetch the firmware for you: | + | # Manual installation (use if step 1 reveals nothing). Open a terminal and type the following command to install b43-fwcutter and fetch the firmware for you: |
sudo apt-get install b43-fwcutter | sudo apt-get install b43-fwcutter | ||
| + | |||
| + | === try a newer liveCD === | ||
| + | Normally we use ubuntu 8.04 on all our systems, but some newer wireless cards are not supported in this version. Use a live CD of the latest ubuntu version (currently 9.04), and see if the card works. | ||
[[Category: Laptops]] | [[Category: Laptops]] | ||
| − | |||
| − | |||
Revision as of 14:31, 1 August 2009
Wireless not working? Try these tips!
look for a physical button
All too frequently, one will spend a whole bunch of time trying to configure a seemingly non-functional wireless only to realize later that there was a much simpler solution. First, look for a button or switch or combination of keys to activate/deactivate the wireless. For example, is there a button above the keyboard? a switch on the side? maybe Fn + F5 turns the wireless on and off?
lspci is your friend
The lspci command is a utility for displaying information about all PCI buses in the system and all devices connected to them. It will tell you about your wireless card, if there is one installed. In particular, it will tell you whether your wireless card has a Broadcom chipset (which, if it does, you'll need to install some stuff - see below).
EXAMPLE OF BROADCOM CHIPSET
ifconfig: am I connected?
The ifconfig command configures a wired network interface. It is a useful command for determining whether or not you're connected to a network AND which network interface is being used to connect (i.e. whether you're connected to a wireless or wired network).
eth0 Link encap:Ethernet HWaddr 08:00:46:0E:8C:D8
inet addr:192.168.2.252 Bcast:192.168.2.255 Mask:255.255.255.0
inet6 addr: fe80::a00:46ff:fe0e:8cd8/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3588 errors:0 dropped:0 overruns:0 frame:0
TX packets:624 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1050713 (1.0 MiB) TX bytes:111359 (108.7 KiB)
This example shows that interface eth0 is connected (because it shows an inet address). To determine whether eth0 is the wired or wireless interface, use iwconfig
iwconfig: no wires!
The iwconfig command configures a wireless network interface. It is a useful command for determining which interface is being used for wireless networking.
eth0 no wireless extensions.
eth1 radio off ESSID:""
Mode:Managed Channel:0 Access Point: Not-Associated
Bit Rate:0 kb/s Tx-Power=off Sensitivity=8/0
Retry limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality:0 Signal level:0 Noise level:0
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
The above example shows 3 important things: (1) that your wireless interface is eth1, (2) that eth0 is your wired network (because it reads "no wireless extension"), and (3) that your wireless is turned off ("radio off"). When you see "radio off" this generally means there's a physical button somewhere on the laptop that is currently in the off position. If you switched on the wireless and then ran iwconfig you might see something like this:
eth1 IEEE 802.11g ESSID:"freegeek"
Mode:Managed Frequency:2.422 GHz Access Point: 00:14:BF:2B:41:1D
Bit Rate:54 Mb/s Tx-Power=20 dBm Sensitivity=8/0
Retry limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality=93/100 Signal level=-34 dBm Noise level=-89 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:4
Note that the ESSID is "freegeek." This means that you're connected to the Free Geek wireless network.
dhclient
The dhclient command will look for a server that will give your laptop a network address. Run this command as a super-user (sudo).
- If you just type dhclient it will try all interfaces (wireless and wired)
- You can specify which interface you would like by typing dhclient [interface]
- EXAMPLE: if you run iwconfig and discover that your wireless interface is eth1, then running dhclient eth1 will only try to connect your laptop to any wireless network. If you specifically want to connect to the "freegeek" wireless network, you can type dhclient eth1 essid freegeek
Broadcom chipset
So you've discovered that your wireless card has a Broadcom chipset, eh? Try these steps:
- System > Administration > Hardware Drivers
- If present, select "Broadcom B43 wireless driver"
- Manual installation (use if step 1 reveals nothing). Open a terminal and type the following command to install b43-fwcutter and fetch the firmware for you:
sudo apt-get install b43-fwcutter
try a newer liveCD
Normally we use ubuntu 8.04 on all our systems, but some newer wireless cards are not supported in this version. Use a live CD of the latest ubuntu version (currently 9.04), and see if the card works.