Wifi stopped working...

Got problems with your B2 or B3? Share and get helped!
DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Wifi stopped working...

Post by DanielM » 02 Nov 2012, 11:32

Hi all.
Today my wireless network suddenly stopped working. I've been digging for hours now and I can't seem to find what's wrong. It might just be something easy, let's see if anyone here has any good ideas:

What happens is that devices (laptops, mobile phones) simply cannot connect anymore. They see the SSID but when trying to connect they try for a while and then gives up. Setting static ip doesn't help. Connecting by wire works fine. I can't see anything useful happening in syslog when trying to connect a device. The only thing I have in my hostapd conf that is not like out-of-the-box is mac address filter (according to my guide at http://wiki.excito.org/wiki/index.php/M ... ss_network), but I tried disabling it to no avail. Also tried a reboot of entire B3 (which spoiled my uptime of several months). I have no encryption whatsoever enabled.

Also checked with inSSIDer and I have normal strength (somewhere around -50 dBm) and I can't see any other wireless networks disturbing.

Kinda out of ideas now. Anyone?

/Daniel

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 03 Nov 2012, 05:21

I've now dug out my old Netgear router, set it up as access point and everything is working perfectly. So the problem this time isn't interference (last time I had similar problems it was my neighbours electric fencing) but something in the B3. What the heck could suddenly cause this kind of problem???

/Daniel

nobody
Posts: 226
Joined: 10 Mar 2012, 14:46

Re: Wifi stopped working...

Post by nobody » 03 Nov 2012, 09:59

Daylight saving time?

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 03 Nov 2012, 11:40

nobody wrote:Daylight saving time?
Time on server is correct, ntp synced. And I guess if that would be the problem it would have stopped working a week ago.

I really hate this kind of strange problems. Don't even know what to start looking for :evil:

/Daniel

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 13 Nov 2012, 02:12

Still struggling with this. Thing is, it not only affects wifi. I've discovered that also when connected on wire (which is also routed through my B3) I get seemingly intermittent network disturbance, like network is completely down for a few seconds and then works again. This started at the same time as wifi stopped working, so I guess it's somehow related.

Any good ideas? Could it be some hardware component failing?

/Daniel

edit: ...or could it have to do with the big upgrade? I see in my apt log that a whole lot of packages updated on 29 of october. If that's the case then question is why did it continue to work some days after the upgrade and why hasn't anyone else reported the same problems...

johannes
Posts: 1469
Joined: 31 Dec 2006, 07:12
Location: Sweden
Contact:

Re: Wifi stopped working...

Post by johannes » 14 Nov 2012, 14:59

I have no good ideas since we don't have other reports, but some long shots:

- make sure you don't have any new nearby equipment (or some old apparatus you have moved closer to the B3) that may disturb wifi. I'm thinking that you didn't place the netgear exactly where the B3 is, and it could be something very local. Wires close to the antennas? Try moving the B3 to another room or part of the room and see if it makes any difference

- try again with the netgear. You never know, if it is some donkey-fence-like error agian it may not have occured during your Netgear test.

- run top and watch it while connecting to wifi, just to see that B3 isn't loaded with some other stuff. A heavily loaded CPU can cause such issues

Otherwise it may of course be some hardware trouble. Since you are a faithful customer and contributor we'd of course be happy to send you a replacement board for testing. Just email me and I'll arrange it.
/Johannes (Excito co-founder a long time ago, but now I'm just Johannes)

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 14 Nov 2012, 16:24

Thanks for your reply Johannes. Answering below...
johannes wrote:- make sure you don't have any new nearby equipment (or some old apparatus you have moved closer to the B3) that may disturb wifi. I'm thinking that you didn't place the netgear exactly where the B3 is, and it could be something very local. Wires close to the antennas? Try moving the B3 to another room or part of the room and see if it makes any difference

- try again with the netgear. You never know, if it is some donkey-fence-like error agian it may not have occured during your Netgear test.
I've really gone through the day it stopped working hour by hour and I didn't move anything at all. Not even the rabbit cage was moved. The B3 is kinda cramped into a little cabinet full of stuff (UPS and fiber stuff), but nothing of that was changed that day. You're correct in that the Netgear isn't in the same place though, could be worth testing moving it. It's been up and working 24/7 last week in it's current position though (and at the same time I've tried B3 wifi without success even once) so I know wifi IS working in the house.
johannes wrote:- run top and watch it while connecting to wifi, just to see that B3 isn't loaded with some other stuff. A heavily loaded CPU can cause such issues
Never seen the cpu load in my B3 get very high. You can see yourself here: http://ideel.nl/bubba/bubba/daniel.bubba/cpu.html (Thanks Ubi :D )

(Now that you say it though, I see in the graph there is a weird cpu spike in week 44 that just COULD coincide with the problem starting. I'll have to investigate that one deeper...)
johannes wrote:Otherwise it may of course be some hardware trouble. Since you are a faithful customer and contributor we'd of course be happy to send you a replacement board for testing. Just email me and I'll arrange it.
Thanks for the offer. My guts doesn't say that it's hardware though. I'll remember the offer though if I don't solve it. What would be REALLY good would be if I could simply buy a B4 instead :D

/Daniel

edit: Ok. Tried now enabling wifi on the B3 and trying to connect with various devices while at the same time watching a top. Except for a few spikes of maybe 50% the usage is always below 5%. Another one to rule out...

edit2: Just noticed that even though the devices doesn't successfully connect, there is according to Munin registered traffic on the interface (see http://ideel.nl/bubba/bubba/daniel.bubba/if_wlan0.html). Anyone knows what Munin looks at exactly?

johannes
Posts: 1469
Joined: 31 Dec 2006, 07:12
Location: Sweden
Contact:

Re: Wifi stopped working...

Post by johannes » 14 Nov 2012, 16:52

Yeah, expected that my longshots was nothing but longshots. Last one then, if you have a spare HDD put that into B3 and reinstall from scratch, just to rule out some setting or other software malfunction (since you don't think it's hardware it must be software, right?). Or I can post you an installed HDD for loan and test?
/Johannes (Excito co-founder a long time ago, but now I'm just Johannes)

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 15 Nov 2012, 13:27

I guess you're right. It won't be a problem finding some old disk at work, problem is getting time to tamper with it. And minimizing the downtime. Guess I'll have to live with Netgear til then. I'll report back!

/Daniel

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 06 Dec 2012, 07:21

Haven't got around to testing with another disk, but I've done some other testing now. Thing is this isn't only wifi not working, it seems also units conected by wire drops connection once in a while. Sometimes everything works again a few seconds later, sometimes network is down for minutes. This happens at the same time for all connected devices, like my B3 simply decides not to talk to internal network.

I tried making a little bash script that pings both external dns server and a device (my Miraclebox) in my house that is always on every fifth second and logs any lost replies, and after having it running for a day in background the external ip hasn't missed one ping but the internal has quite a lot. And the missed packages comes in chunks like I described above, so sometimes it gets no answer for a minute. At least one of those occations coincides with a time when I noticed that my laptop didn't reach network.

So now I'm digging logs and trying to find anything that matches the timestamps when I know internal network is down. There gotta be something happening!

/Daniel

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 31 Mar 2013, 12:48

Since I had some kind of vague hope that this COULD have something with daylight savings time to do (may the person that invented dst burn in hell), I tried today. Wasn't very surprised when it still didn't work.

Anyway, I still think this have something to do with packages that were updated just the days before everything stopped working, so I'm now trying downgrades of packages. We'll see how that turns out...

I live with the hope that I some day can get rid of the ugly Netgear AP that currently lives on my living room floor...

/Daniel

edit: I've now downgraded every package that could have any connection whatsoever with this to the versions I had installed before it stopped working. No change. So I guess this HAS to be hardware related, something just broke. Guess I really have to switch disk and reinstall. Just wish my days had more hours...

pompopom
Posts: 50
Joined: 13 Dec 2012, 16:45

Re: Wifi stopped working...

Post by pompopom » 25 Apr 2013, 07:51

For what it's worth:
If I understood well in some reading on this forum, Wifi and internal Lan are closely related together inside the B3 (by some form of bridging?). I suppose your wired LAN is connected to some switch.
- did you try to change the patch cord from B3 to switch?
- use another port on your switch?
- switch the switch?

I had somewhat same problem with an equipment at work not so long ago, searched for a few days and finally it was a patch cable within the structured cabling which had issues.

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 25 Apr 2013, 08:07

Thing is, I finally got things to work. It seems this was a combination between three problems:

1. Some kind of hw fault on my B3 mother board. Excito sent me a new one. I've now sent the old one back, with any luck Excito can tell me exactly what's wrong with it. Or they'll just ditch it, that's fine for me too :D

2. Some sw problem with packages that I upgraded from the repository in the end of october last year. I've now downgraded all of them and I will upgrade dem one by one (and wait a few days in between) until I find out which one is the problem.

3. My neighbours donkey fence. Seems somehow they sometimes does something with it that makes it a huge jamming device for my wifi. Guess it has with grounding to do.

I hate problems with too many factors, it's always a "%#"¤ finding what's really wrong.

/Daniel

johannes
Posts: 1469
Joined: 31 Dec 2006, 07:12
Location: Sweden
Contact:

Re: Wifi stopped working...

Post by johannes » 25 Apr 2013, 08:14

Hehe, that Donkey fence again. Never ending story. :D
We tested your board today and actually found one HW error, the eSATA port did not work. Which probably is very unrelated, right? Otherwise we can't find anything wrong. Glad it works now anyways. :)
/Johannes (Excito co-founder a long time ago, but now I'm just Johannes)

DanielM
Posts: 637
Joined: 28 Mar 2008, 06:37
Location: Sweden

Re: Wifi stopped working...

Post by DanielM » 25 Apr 2013, 14:23

johannes wrote:Hehe, that Donkey fence again. Never ending story. :D
We tested your board today and actually found one HW error, the eSATA port did not work. Which probably is very unrelated, right? Otherwise we can't find anything wrong. Glad it works now anyways. :)
Haha... That's kinda funny... The eSATA port is the only port on that board that i never used for anything :D

Well, I really can't rule out the possibility that the hw was never any problem, it might have been only software and fences. Too many factors here.

But as said, I will come back when I know which package to blame, see if we can find out then exactly what's the problem.

/Daniel

Post Reply