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After rebooting, sometimes when I run iwlist ath0 scan, I get No Scan Results (meaning no access points found) whether the AP is 1 foot, 10 feet or 20 feet away.
So I reboot and eventually iwlist ath0 scan finds my Access Point. Reboot again and it can't find it.
Normally I would post this in the Wireless Networking, but since I can get it to work perfectly under Ubuntu 7.04, I felt this was better suited to the Slackware forum.
Laptop is Acer Aspire 5050 with Atheros 5005 built-in.
I'm not even trying to connect to it. Just find it. I've experienced this with both the latest madwifi and ndiswrapper drivers.
In Ubuntu, I am using WPA-PSK with TKIP with disabled SSID broadcasting and have zero issues finding the AP, connecting and staying connected.
I updated my router firmware and will be updating my laptop BIOS (but it doesn't really explain why it works in Ubuntu..)
Can anyone think of what might be wrong? I suspect it's an issue with the way the default Slackware Kernel is assigning resources to the card (luck of the draw) and maybe there is an IRQ conflict. I don't see anything wrong in /var/log/messages, /var/log/syslog and dmesg.
I have read all the madwifi, ndiswrapper user and troubleshooting docs, but I don't see my issue as a popular one. If it's loading the driver successfully and there are no errors anywhere, it should be working, that's what's really bugging me.
How do you know the driver is loaded successfully. (Is ath0 shown in /proc/net/wireless?) Did you say "ifconfig ath0 up"? If not, try that. What does "iwconfig ath0" say? Try supplying any keys, an essid or other info using iwconfig.
I will never get why people disable SSID broadcast. You are only disabling the regular beaconing of the SSID. It will still be broadcast in response to a probe request and the wireless signal is visible no matter what. No security is gained and it introduces connection difficulties under some circomstances. The only thing SSID broadcast disable does is make it harder for others to avoid the same channel.
Off my soapbox, now.
First, make sure you don't have both ndiswrapper and madwifi loading concurrently. Since you mention ath0, and since ndiswrapper would be using wlan0, let's stick with madwifi for now.
# modprobe -r ndiswrapper ath_pci
# modprobe ath_pci
If you turn off encryption, can you connect to your router manually?
# iwconfig ath0 essid your_ssid
# dhcpcd ath0
If that works, we should assume that the wpa_supplicant is misconfigured or not working properly.
Start by running it manually:
# /wpa_supplicant -w -c/etc/wpa_supplicant.conf -Dwext -iath0
Note the lack of the -B (background) option. This will show you connect messages or errors. You can also add the -d or -dd option for increased verbosity.
Lastly, post the contents of your /etc/wpa_supplicant.conf and /etc/rc.d/rc.inet1.conf files (with secret info concealed) so that we can look for problems there.
How do you know the driver is loaded successfully. (Is ath0 shown in /proc/net/wireless?) Did you say "ifconfig ath0 up"? If not, try that. What does "iwconfig ath0" say? Try supplying any keys, an essid or other info using iwconfig.
I didn't check /proc/net/wireless, but ath0 is up, otherwise iwlist ath0 scan reports interface doesn't support scanning. iwconfig ath0 shows the device. I shouldn't need to supply any keys/essid's when scanning for APs right? I tried Kwificonfig (or whatever it's called) with broadcasting and no security and it found my AP, connected, received an IP with dhcpcd, it just kinda died.
I will never get why people disable SSID broadcast. You are only disabling the regular beaconing of the SSID. It will still be broadcast in response to a probe request and the wireless signal is visible no matter what. No security is gained and it introduces connection difficulties under some circomstances. The only thing SSID broadcast disable does is make it harder for others to avoid the same channel.
Off my soapbox, now.
First, make sure you don't have both ndiswrapper and madwifi loading concurrently. Since you mention ath0, and since ndiswrapper would be using wlan0, let's stick with madwifi for now.
# modprobe -r ndiswrapper ath_pci
# modprobe ath_pci
If you turn off encryption, can you connect to your router manually?
# iwconfig ath0 essid your_ssid
# dhcpcd ath0
If that works, we should assume that the wpa_supplicant is misconfigured or not working properly.
Start by running it manually:
# /wpa_supplicant -w -c/etc/wpa_supplicant.conf -Dwext -iath0
Note the lack of the -B (background) option. This will show you connect messages or errors. You can also add the -d or -dd option for increased verbosity.
Lastly, post the contents of your /etc/wpa_supplicant.conf and /etc/rc.d/rc.inet1.conf files (with secret info concealed) so that we can look for problems there.
(Sorry for the rant - it's a pet peeve.)
I understand and agree about the SSID broadcasting. It does prevent all the XP users from casually finding it with Windows built-in tools though.
Anyways, I did try with no security and broadcasting - no good. Only one driver at a time - madwifi for most of my testing. I just wanted to rule out the driver..
I am going to try connecting using iwconfig (with no security) instead of the kde wificonfig tool. I read that I need to be able to scan/see the access point before it will work, that being said, is it still possible to connect to the AP when scanning for it fails?
I'm using the same wpa_supplicant.conf settings for both distros. I am not at home, but I will post it. It's very basic, worked in Slackware 11 (2.4) at one time and I haven't changed since the days it worked in 11/2.4.
I have not used rc.inet1.conf or rc.wireless/rc.wireless.conf files for any wifi networking. I've looked at those files and it just seems cleaner and easier to use wpa_supplicant for my wifi connections.
I can post the rc.inet1.conf file. As it currently exists, I have not configured any networking options. Normally once I get wifi connected, I just run dhcpcd ath0 and it worked in 11/2.4...but that being said, my 11/2.4 install hasn't been working anymore either for whatever reason since nothing changed there either.
Alien_Bob can chime in here, but as I understand it inet1.conf is the now preferred place for configuring wireless instead of rc.wireless.opts. It changed a lot from 10.2 to 11.0.
When you say "I've looked at those files and it just seems cleaner and easier to use wpa_supplicant for my wifi connections." do you mean that you're running wpa_supplicant from the command line or calling it in rc.local? How is it starting? If you grep for wpa_supplicant in ps aux, and it's running with the -B switch, try running it in the foreground as mentioned above for messages. (Not an issue just yet, since we can't connect without security enabled.)
For SSID broadcast disable, I've seen folks get results with ap_scan=2 in /etc/wpa_supplicant.conf
As mentioned above, try ifconfig ath0 up before using iwconfig and dhcpcd. Don't know why, but sometimes, it matters.
Alien_Bob can chime in here, but as I understand it inet1.conf is the now preferred place for configuring wireless instead of rc.wireless.opts. It changed a lot from 10.2 to 11.0.
When you say "I've looked at those files and it just seems cleaner and easier to use wpa_supplicant for my wifi connections." do you mean that you're running wpa_supplicant from the command line or calling it in rc.local? How is it starting? If you grep for wpa_supplicant in ps aux, and it's running with the -B switch, try running it in the foreground as mentioned above for messages. (Not an issue just yet, since we can't connect without security enabled.)
For SSID broadcast disable, I've seen folks get results with ap_scan=2 in /etc/wpa_supplicant.conf
As mentioned above, try ifconfig ath0 up before using iwconfig and dhcpcd. Don't know why, but sometimes, it matters.
Yes, I normally run wpa_supplicant -dd -D madwifi -iath0 -c/etc/wpa_supplicant.conf for testing.
I've tried setting SSID to broadcast enabled and no security. I tried iwconfig ath0 essid test (only madwifi) & iwconfig wlan0 essid test (only ndiswrapper) and while i receive no errors after running the command, dhcpcd times out.
I want to focus on a connection without the WPA-PSK for now. What else can you recommend? I did check my rc.inet1.conf file and it's completely vanilla - zero modifications since installation.
Post the output of iwconfig ath0 after you've set the SSID. That will tell us if it's associating. Have you tried a static IP with gateway and DNS servers?
In fact, if you're associating with the AP, but not getting an IP address, try adding a gateway.
# route add default gw 192.168.1.1 (assuming that's the IP of the router)
Then, delete all the junk in /etc/dhcpc and re-run dhcpcd.
Post the output of iwconfig ath0 after you've set the SSID. That will tell us if it's associating. Have you tried a static IP with gateway and DNS servers?
In fact, if you're associating with the AP, but not getting an IP address, try adding a gateway.
# route add default gw 192.168.1.1 (assuming that's the IP of the router)
Then, delete all the junk in /etc/dhcpc and re-run dhcpcd.
Ok, this is what I ran:
iwlist ath0 scan (to ensure it's seeing the AP and this boot it did)
iwconfig ath0 essid test
ifconfig ath0 192.168.1.200 netmask 255.255.255.0 up
route add default gw 192.168.1.1
I then tried to run iwlist ath0 scan and "No scan results" now. Also, i can't ping the AP. I see the "Not associated"...i guess that's what you were looking for?
I was able to boot up, go straight into KDE and using KWifiManager, I connected to my AP and dhcpcd ath0 actually obtained an IP, but that's where it ended. I can't ping anything but the localhost.
Well, the good news is that you're associated with the AP. All looks well on the wireless piece.
You said this worked under Ubuntu - same box and wireless device? Just wanting to rule out something silly on the router end like MAC address filtering or a too-small DHCP address pool. Check the router logs, just for grins.
Try entering you ISP's DNS servers in /etc/resolv. Those should come from the dhcp server, but I'm looking for any port in the storm at this point.
Well, the good news is that you're associated with the AP. All looks well on the wireless piece.
You said this worked under Ubuntu - same box and wireless device? Just wanting to rule out something silly on the router end like MAC address filtering or a too-small DHCP address pool. Check the router logs, just for grins.
Try entering you ISP's DNS servers in /etc/resolv. Those should come from the dhcp server, but I'm looking for any port in the storm at this point.
Yep, works great under Ubuntu, same Laptop. No MAC Address filtering and DHCP pool is large enough. Checked the router logs and nothing regarding blocking it. I was going to enter in the ISP DNS IPs but I wanted to start with pinging my internal devices on the same subnet and since that's not working...
I really appreciate the help. I'm totally at a loss here. I want to see some error messages, but nadda. Any idea why its connecting to the AP in KDE vs iwconfig command-line tools?
NOTE: I had to disable SMP support on Slack 12 due to those timer issues where the system stalls unless I keep pressing a key to push it along. Unless you have another suggestion, enabling SMP isn't really an option cause then the laptop is completely useless. I only notice this since the 2.6.21.1+ kernels. Dynamic Tick? HPET?
I'm also posting my iwconfig from Ubuntu for comparison (WPA-PSK enabled and working):
*********************************
ath0 IEEE 802.11g ESSID:"test" Nickname:""
Mode:Managed Frequency:2.447 GHz Access Point: 00:11:95:CC:CF:1F
Bit Rate:12 Mb/s Tx-Power:16 dBm Sensitivity=0/3
Retryff RTS thrff Fragment thrff
Encryption key:******************************* Security mode:restricted
Power Managementff
Link Quality=68/94 Signal level=-26 dBm Noise level=-94 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
It appears that my initial suspicions were correct. The issue was interrupt related. I re-enabled SMP support and the APIC was enabled for IRQs, which then moved the wifi0 to it's own IRQ.
I was able to connect to my AP and receive a DHCP lease successfully.
Now, I still have the problem with the timer. Does anyone know how to fix that? Is there a kernel option I can disable? I've tried HPET=disable, but that didn't do anything for me.
Big thanks to 2Gnu for being persistent in trying to resolve my issue and teaching me a few more wireless tricks in the process.
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