Realtek 8187b wireless card does not work properly under fedora 10

flauser · 12-16-2008, 07:34 PM

Hello everyone, after configuring my wlan0 interface for a Realtek RTL8187B card, to use DHCP on fedora 10, it actually manages to grab a proper IP address, default gateway address, and primary DNS Server address, as expected. I confirmed the connection with my DSL modem/router was established out of many different reasons, amongs others the fact that arp -n gives the correct MAC address for the router, which tells me there is at least connectivity. To put it simply, the SO is doing everything right except for the last thing: it detects a network, connects me to it after I select it, it configures wlan0 through DHCP, but when I try to access the internet, nothing, it does not even ping www.google.com or the gateway itself (ip: 192.168.1.254) correctly.

I will try to post some info to see if any of it helps hunt down the problem:

Code:

prompt# dmesg | grep -i wlan0

ADDRCONF(NETDEV_UP): wlan0: link is not ready
wlan0: authenticate with AP 00:14:95:5e:70:32
wlan0: authenticated
wlan0: associate with AP 00:14:95:5e:70:32
wlan0: RX AssocResp from 00:14:95:5e:70:32 (capab=0x431 status=0 aid=7)
wlan0: associated
ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
wlan0: no IPv6 routers present

just in case it's a firewall problem, though it doesn't seem to be:

Code:

prompt# iptables -t filter -L

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
ACCEPT     all  --  anywhere             anywhere  
ACCEPT     icmp --  anywhere             anywhere            
ACCEPT     all  --  anywhere             anywhere            
ACCEPT     tcp  --  anywhere             anywhere  
REJECT     all  --  anywhere             anywhere

the next part is the kind of thing that convolutes the mind of any newbie, such as myself:

Code:

prompt# ifconfig wlan0

wlan0   Link encap:Ethernet  HWaddr 00:08:54:AF:5C:0E  
        inet addr:192.168.1.141  Bcast:192.168.1.255  Mask:255.255.255.0
        inet6 addr: fe80::208:54ff:feaf:5c0e/64 Scope:Link
        UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
        RX packets:376 errors:0 dropped:0 overruns:0 frame:0
        TX packets:24 errors:0 dropped:0 overruns:0 carrier:0
        collisions:0 txqueuelen:1000 
        RX bytes:22144 (21.6 KiB)  TX bytes:5441 (5.3 KiB)

prompt# ifconfig wlan0  # after having pinged www.google.com, getting no response at all

Linux localhost.localdomain 2.6.27.5-117.fc10.i686 #1 SMP Tue Nov 18 12:19:59 EST 2008 i686 i686 i386 GNU/Linux
wlan0   Link encap:Ethernet  HWaddr 00:08:54:AF:5C:0E  
        inet addr:192.168.1.141  Bcast:192.168.1.255  Mask:255.255.255.0
        inet6 addr: fe80::208:54ff:feaf:5c0e/64 Scope:Link
        UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
        RX packets:911 errors:0 dropped:0 overruns:0 frame:0       
        TX packets:31 errors:0 dropped:0 overruns:0 carrier:0
        collisions:0 txqueuelen:1000 
        RX bytes:48630 (47.4 KiB)  TX bytes:5989 (5.8 KiB)

I posted the last part only to show that pinging www.google.com does not give a result, and yet 'ifconfig wlan0' shows that the interface has indeed received and transmitted packets.

By the way, the interface is using driver rtl8187, I hope someone has an idea about what else could be the problem. Please tell me if there is any more info I should post, I tried to be as descriptive as possible. Thanks in advance.

PTrenholme · 12-17-2008, 12:47 PM

Assuming you're using a GUI, have you tried the network applet? (In GNOME, it's on the task bar towards the upper, right side; on KDE, it's at the lower, right side.)

The point is that Fedora 10 defaults to using built-in communication management tools, and, basically, depreciates use of the if* and iw* tools.

On my F10 KDE system, I just left-click on the network icon, pick the AP to which I wish to connect, and click on it. If passwords are needed to connect, I get prompted for them, and then get connected. (The point about passwords was because, from what you posted, it looked like you were running an open AP.)

flauser · 12-17-2008, 01:49 PM

Thanks for the post. I have tried to use the network applet to configure the connection but it has not helped. Originally I had already tried to work with a shared key and provided the right key, but the interface does not connect when I do that, so far I've only been able to connect it as if it were connecting to an open system. By the way, the topology here is rather simple: there is one DLS modem/router which is also the only Access Point for the internal network. I´m wondering about wether the driver is the right one, is there any chance some driver got ahold of the wireless card but is unable to manage it properly? That seems unlikely considering everything else is working fine (DHCP, ARP, it detected 2 different network SSIDs including the one it should connect to, etc). Should DHCP work even if something with encryption is the matter? By the way, I've just finished installing Ubuntu, and after using the same GUI to configure wlan0, I get the same results: I get connected to the network but cannot visit any web pages, and when using a shared key, I can't even connect. That tells me it's not a problem with the distro. But in that case, I feel even more lost, sigh :s.

PTrenholme · 12-17-2008, 03:26 PM

Can you connect to the DSL modem via cable? If so, verify that it's set up the way you think it's set up (probably is, but it never hurts to check), and look at the log on the modem (assuming you've turned on logging) or, if logging is turned off, turn it on.

The modem log should tell you what kind of connection you're getting and why you're not getting through.

One other thing you can try: Instead of using a non-routable address (10.*.*.* [10/8 prefix], 172.[16-32].*.* [17.16/12 prefix], or 192.168.*.* [192.168/16 prefix]) try using a routable one (making sure your firewall doesn't let local traffic into the Internet) if it's possible that you've got a switch in your network that's blocking non-routable addresses. (Again, given your network description, this is no too likely, but, hey, I grasping at straws.

)

flauser · 12-17-2008, 06:27 PM

I have tried to ping to a routable, external IP address, to no avail. I also must mention everything works fine under Win XP, my problem is I'm trying to replace Windows with any Linux distro (really, any, I'm desperate here

). By the way, under Windows the authentication option that is selected is "Open System" and yet it still demands a key. Linux also demands a key with the "Open System" option, though the difference is it does not yet work under Linux.

By the way, I'm posting one of the few entries in the log that refer to my machine. It now has an IP of 192.168.1.10 because that is the static private IP address it has under Windows, and I thought the wireless router might bind a MAC to a static IP, and so I decided to configure wlan0 to have the same static IP address under Linux. Alas, that has produced no different result.

Quote:

INF 2008-12-17T17:17:13-06:00 fw,fwmon: src=200.158.140.213 dst=192.168.1.10 ipprot=17 (layer 4 info unknown) Unknown inbound session stopped

I'm no networking expert yet but the above attached entry in the modem's log just seems to be something from NAT, which I probably received after I logged into Windows. Otherwise, I found nothing interesting in the logs.

By now I'm considering the option of just buying another wireless card, but it troubles me to think I'd be unable to solve this problem with a more elegant solution. After all, what if the problem does not lie in the card's model or make? Then I'd just be wasting more money and not really shedding more light into this tricky problem.

PTrenholme · 12-18-2008, 02:09 PM

If you're really catholic about the distribution, check out the Live CD list and try a few to see if they can connect.

flauser · 12-18-2008, 04:52 PM

Hey, thanks! I think I'll give it a try. Someone just suggested to me too that I should look into the possibility of a bad driver being responsible for a present but limited connectivity. Whatever works! I just want to get through this problem.

shpenat · 12-27-2008, 05:05 AM

Little bit late, but still.... Check your routing table. Especially if you have more than one network card.

flauser · 12-27-2008, 11:13 AM

Hey, thanks for the advice. The firewall does not seem to be the problem. In fact I posted at least the status of the filter table above on the very first message of the thread. Actually, I've resolved the issue for the most part. Installing Fedora Core 10 enabled the detection of the device and it even allows me to connect to any network. The problem is I have to get closer to the wireless router in order for me to be able to surf the web. That is definitely due to the driver Linux uses, considering that before switching over to Linux, I was able to at least google for things even if the signal was weak. Then again, the network card itself is, I've been told, not the best in the market. It might not hurt to spend a little to get a wireless card that performs better.

pentode · 12-27-2008, 01:51 PM

Just to be sure: If you have both a wired Ethernet and a wireless connection to the same subnet, you will have problems. You'll need to unplug or take down the wired interface when using the wireless.

flauser · 12-28-2008, 10:48 AM

Good point, thanks for the tip. I'll be sure to do that.