Wireless routing trouble

Frantic · 2009-02-24 20:36:31

I just installed arch on my new desktop PC, among a series of trouble this is my last one that I cannot find a way to resolve.

Once every hour to once very few minutes, with a duration of under 2-3 minutes, my box will refuse to send stuff to the gateway (which is also the access point I use), but still send stuff to the other computers thru the same access point.

I got to this conclusion after starting 3 pings in background: router, intranet computer, external host (yahoo.com).
When this weird phenomenon occurs, I will get replies form the intranet computer, but not from the other 2 pinged hosts.

I am sure it's not a router issue because I have also ran these 3 ping scenarios on a machine connected by ethernet and on my laptop (arch, same wireless configuration as the PC with the problem, except that it's a iwl3945 driver), both work fine in the same time my desktop PC fails.

Another weird thing I have noticed, is that when I get these timeouts, if I do a "sudo route", it will print my subnet route, but hang before printing my other route (the one with the gateway). (Just to be clear, this only happens while I get the timeouts. After the normal operation resumes, route will finish the output instantly). This hang can be upto a minute.

There is nothing new in /var/log/messages during this phenomenon.
I have also noticed that if I restart the wpa_supplicant process, the timeouts occur less often for an hour or so.

Does anyone know what's causing this?

Here's my "route" output:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.100.0   *               255.255.255.0   U     0      0        0 wlan0
default         192.168.100.1   0.0.0.0         UG    0      0        0 wlan0

I have the following wireless card:

03:01.0 Network controller: RaLink RT2561/RT61 802.11g PCI
        Subsystem: RaLink EW-7108PCg
        Flags: bus master, slow devsel, latency 32, IRQ 22
        Memory at f9ff8000 (32-bit, non-prefetchable) [size=32K]
        Capabilities: <access denied>
        Kernel driver in use: rt61pci
        Kernel modules: rt61pci

I use it to connect to a WPA2-PSK wifi (hidden ssid, AES encryption).
I connect to the wireless with the following script:

wpa_supplicant -Dwext -iwlan0 -c /etc/wpa_<wifiname>.conf -dd &
dhclient wlan0

Here's the .conf I use:

ctrl_interface=/var/run/wpa_supplicant
ctrl_interface_group=wheel
ap_scan=1
update_config=1
network={
    scan_ssid=1
    ssid="<the_ssid>"
    psk=the_wpa_key
}

This works. Lan is up, inet is up.

Last edited by Frantic (2009-02-25 17:48:36)

Frantic · 2009-02-25 13:06:29

noone?

Frantic · 2009-02-25 17:49:42

hmm quakelive is out, windows only, and my wifi is failing in linux.. if I think about it, vista is not so bad

arew264 · 2009-02-26 01:54:41

When route hangs for me, it normally means I'm having connection issues of some sort, and route can't actually find the default gateway on the network (apparantly it does check to make sure it's there somehow).
When this happens to you, does your connection eventually start working again, or do you just have to shut it down and connect again? Are there other wireless networks in the area running on the same channel as yours?
Do you have another network adaptor that could be coming online somehow and gumming things up (if it comes online, it'll show up when you run `ifconfig` with no arguments)?

Frantic · 2009-02-26 02:17:02

Yep, there are actually a lot more computers running on that same AP.
When I was checking to make sure it's not a problem with the router I used the troublesome PC, my laptop and a intranet server over SSH. There are alos 10ish computers running at the same time on that same intranet at the same time.

What happens to me is that I can access anything else on the intranet except the gateway.
I don't have to restart it, it will eventually fix itself, but I noticed that if I do restart wpa_supplicant it will get fixed instantly and I get a lot less trouble for a short while.

I do have the ethernet NIC that is up but idling, now that you mentioned it, it's up and running, but no wire, might be that causing the trouble.
What I have tried was to negate both interfaces in rc.conf (!wlan0 !eth0), this didn't help. I'll also try doing a ifconfig down eth0.

Funny thing is that I'm running the same configs on my laptop, eth0 up, connecting thru wlan0, same apps, no special configs I know of, working right.

arew264 · 2009-02-26 02:22:41

If you check `dmesg | tail` or /var/log/everything.log while you're having trouble, are there any messages about the wireless driver losing it's connection or anything?
I'm not sure where to go from here because I've never touched the RaLink driver. Does your laptop also use it?

Frantic · 2009-02-26 02:25:42

My laptop uses iwl3945 .
I have checked dmesg and everything.log, nothing new there when this happens or when it recovers.
I've also checked the wpa_supplicant output (it occasionally does "rekeying" whatever that is, but it doesn't coincide with the periods of trouble).

arew264 · 2009-02-26 02:27:13

This may not be possible because your AP is being used by a bunch of other computers, but if you disable WPA, does everything work consistently?

Frantic · 2009-02-26 02:31:26

Even if I find out it will work without encryption, it still won't be of much help because I need to use it with wpa

But I'll try that, I have to get it alone when noone else needs to use it, sometimes my problem doesn't show for like an hour.

Mean while if you have any other ideas please go ahead and let me know

Frantic · 2009-02-28 16:37:29

zzzZZZZ

arew264 · 2009-02-28 22:08:48

I don't really have anything else you can try, except maybe installing compat-wireless and trying that. I'm pretty sure the wpa_supplicant package is the latest version...

ao · 2009-03-01 08:23:36

"it will print my subnet route, but hang before printing my other route (the one with the gateway)."

I've found this is the case when DNS is not working. Try "route -n" and/or pinging the IP of yahoo.com continuously, versus the domain?

Hope it helps

Frantic · 2009-03-01 17:28:43

Yep, route -n was working, so I added my gateway to /etc/hosts, now route works instantly, but the routing still doesn't work.

lymphatik · 2009-03-08 14:37:54

Did you figured out how to solve this? Because I have to ping atleast 3 or 5 times google.com to get internet.

kgas · 2009-03-08 15:56:53

http://bbs.archlinux.org/viewtopic.php? … 46#p458346. This thread may help you.

Frantic · 2009-03-08 17:36:50

nope, I haven't figured it out yet

kgas: that thread doesn't help

Arch Linux

#1 2009-02-24 20:36:31

Wireless routing trouble

#2 2009-02-25 13:06:29

Re: Wireless routing trouble

#3 2009-02-25 17:49:42

Re: Wireless routing trouble

#4 2009-02-26 01:54:41

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#5 2009-02-26 02:17:02

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#6 2009-02-26 02:22:41

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#7 2009-02-26 02:25:42

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#15 2009-03-08 15:56:53

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#16 2009-03-08 17:36:50

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