2 wifi cards - unable to use the second to connect!

[su]

Hi!
I have a laptop with 2 wifi cards (1 on board and 1 usb).
OS: Kubuntu 9.04
I use network manager to connect to the AP.
I can see both interfaces (wlan0 and wlan1).
When I configure my wireless network everything is OK and connects successfully!
After that I found out that the connection is established using wlan0 interface (on board).
Then I want also to connect with the second wifi card (usb), but I don't know how!!
At the wireless settings tab there is my wireless network configuration but there is no option to associate it to a specific interface. >

Can you please advise me what to do to use the other interface? (usb wifi card)

I noticed also that the network manager has 2 check boxes to enable or disable my wifi cards. When I uncheck the first box it automatically unchecks the second! So both of them disabled!

Thanks in advance

[sithlord48]

Re: 2 wifi cards - unable to use the second to connect!

this could be an issue with the network manager.. i have tried to do this w/ one wired and one wifi but what happens there is that it will drop one connection to activate the other....

you can manually set the interface by editing the file

/etc/network/interfaces

[url=http://www.cyberciti.biz/faq/setting-up-an-network-interfaces-file/]check this page for some info on the file

[su]

Re: 2 wifi cards - unable to use the second to connect!

I install WICD and it's better!
Now I can configure at preferences the interface I want to use but I still have the problem that I can't use both of the wifi card at the same time!!

Isn't it wired?

The concept of the networking implementation is to use only one interface to connect?

If anyone has an answer - workaround please reply!

Thanks

[flarson]

Re: 2 wifi cards - unable to use the second to connect!

Are you trying to use both cards on the same subnet at the same time? If so, have you done anything to let the system know which interface it should use to contact the network?

[su]

Re: 2 wifi cards - unable to use the second to connect!

No!
There is no option to choose both of the wifi cards at the same time!
If I want to use lan and the wlan connection at the same time is ok!
Now I use WICD and there is option to specify 1 lan and 1 wlan only!
I can't specify 2 wlan at the same time!!

I don't know what to do to solve this...puzzle!!

[ukchucktown]

Re: 2 wifi cards - unable to use the second to connect!

You are not allowed to activate two interfaces at the same time to the Internet using WICD or NetworkManager and for good reason: how does the system route the IP packets across both interfaces? As a general rule, you must statically define the routing when using two interfaces. It has nothing to do with the implementation of WICD or NetworkManager, it's basic IP routing. If you want a complex set-up disable the network managers on your system and configure the network manually using the /etc/network/interfaces file. You can start by running "man interfaces" in a terminal to learn how the network is actually configured in Linux. GUIs hide all the fun stuff. You can't do anything cool with the GUI but you can if you learn how to manipulate /etc/network/interfaces.

Cheers, UK

[su]

Re: 2 wifi cards - unable to use the second to connect!

I didn't say internet! :P
Wlan0 interface is the internet connection and Wlan1 is just Local LAN.
What about the routing if you have 1 wired and 1 wireless connection?
You can accomplish this with Network Manager or WICD!!!
Don't you think so?
Configuring manually is ok but you need more time to do so!
Instead, using GUI it's a few clicks..
If you want to setup WPA or WPA2 it's harder!!
ok ok.. I know some things must be done with the... hard way..
If there was any other better solution it would be better!!

[ukchucktown]

Re: 2 wifi cards - unable to use the second to connect!

WICD will not connect both my interfaces (wired and wireless) at the same time. Just to make sure I confirmed it with ifconfig. When I activate my wireless the wired connection is disabled. If wlan0 is Internet and wlan1 is a local LAN you can enable both but you'll need to disable the network managers and do it yourself in /etc/network/interfaces. Also, on wlan1 you will want to define the IP statically and add the necessary route commands in your interfaces file. When it comes to routing there is no difference between wireless and wired. A wired interface is usually eth0 and wireless wlan0. Routing is higher up in the networking stack. How you configure the interface in /etc/network/interfaces is different between a wired and wireless but not the routing. Try typing route -n in a terminal window. That will show your routing table.

UK

[ukchucktown]

Re: 2 wifi cards - unable to use the second to connect!

One final comment, if you want a GUI, a program I always liked is Firestarter. It won't configure your interfaces but it will assist you in other ways if you are new to IP routing and firewalls. It is a Gnome application so you know. I'm not familiar with anything as good in the KDE space.

UK

[su]

Re: 2 wifi cards - unable to use the second to connect!

I'll give it a shoot!

Thank you!

[muzicman0]

Re: 2 wifi cards - unable to use the second to connect!

You are not allowed to activate two interfaces at the same time to the Internet using WICD or NetworkManager and for good reason: how does the system route the IP packets across both interfaces? As a general rule, you must statically define the routing when using two interfaces. It has nothing to do with the implementation of WICD or NetworkManager, it's basic IP routing. If you want a complex set-up disable the network managers on your system and configure the network manually using the /etc/network/interfaces file. You can start by running "man interfaces" in a terminal to learn how the network is actually configured in Linux. GUIs hide all the fun stuff. You can't do anything cool with the GUI but you can if you learn how to manipulate /etc/network/interfaces.

Cheers, UK

I don't think this is true. There may be a reason, but it has nothing to do with IP routing. Each NIC would have it's own IP and MAC address, so IP routing would send packets to whichever interface was listed as the source IP or destination IP, depending on direction of traffic. and even at the DataLink layer, each interface would have a unique MAC.

mm0

[flarson]

Re: 2 wifi cards - unable to use the second to connect!

This is one use of the metric. Larger metric says to prefer the other interface.

[su]

Re: 2 wifi cards - unable to use the second to connect!

I know for sure that windows have metric to choose how to send a packet according routing table. 8)
Does Linux have a similar metric?
If so, only with CLI you can config it?
It should be an automated GUI for new bees to Linux, don't you think?

[flarson]

Re: 2 wifi cards - unable to use the second to connect!

If so, only with CLI you can config it?
It should be an automated GUI for new bees to Linux, don't you think?

No, I don't. I think if people want to maintain their dependence on GUI tools they should use Windoze. However, I am sure you will find many people in this forum who agree with you.

[su]

Re: 2 wifi cards - unable to use the second to connect!

To make clear my opinion about this I have to say that it should be an easy way(GUI) to do the basic things and if you want more complicated things then do it manually(CLI)

I don't think that connecting to two networks is so complicated!

Also if it's easy to do so, then more people will change from Windows to Linux and find out a better OS!

This is just an idea to make network managers a bit better, not to substitute CLI!