# [SOLVED]Centrino Wireless-N 2230 - Unstable Connection

## Holysword

I am having problems with dropping connection every now and then.

My wireless board is

```

08:00.0 Network controller: Intel Corporation Centrino Wireless-N 2230 (rev c4)

```

I've heard that N-1000 had a problem in which the connection would drop randomly:

http://unix.stackexchange.com/questions/90687/recurrent-loss-of-wireless-connectivity/90689#90689

Is this still the case for N-2230? If so, how can I fix it? I don't have a iwlagn module (it uses iwlwifi; is it the same thing?

Thanks in advance!

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## eccerr0r

I'm using iwlwifi on my N2230, connection is fairly stable though I only use it with a select few wifi APs (namely my own...)

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## Holysword

 *eccerr0r wrote:*   

> I'm using iwlwifi on my N2230, connection is fairly stable though I only use it with a select few wifi APs (namely my own...)

 

I am also using my own AP.

Perhaps you could share your .config?

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## eccerr0r

Not really sure it's a kernel configuration problem you're seeing.  I do have to say the signal is kind of weak if I have the screen on my laptop closed (like if I were transporting it and the screen is parallel to the ground), but it's fine when it's opened (as if I were using it).

I'm currently using the Actiontec Q1000's wifi.  It too does not have 5GHz, but does support 802.11n.  And it's on the same floor as where I'm using the laptop.

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## Holysword

 *eccerr0r wrote:*   

> Not really sure it's a kernel configuration problem you're seeing.  I do have to say the signal is kind of weak if I have the screen on my laptop closed (like if I were transporting it and the screen is parallel to the ground), but it's fine when it's opened (as if I were using it).
> 
> I'm currently using the Actiontec Q1000's wifi.  It too does not have 5GHz, but does support 802.11n.  And it's on the same floor as where I'm using the laptop.

 

I experience the instability when using the laptop; namely skype is ultra problematic.

When playing games I get disconnected a few times too, but skype is far worse.

I have no idea how ot debug this kind of thing to make sure it is not my ISP's fault.

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## eccerr0r

Ethernet is the easiest way to tell if it's your ISP's fault.  

Also the closer you are to your AP the less likely you'll have a problem with interference.  You can also run ping against your AP during the time you have problems (or you can keep it running all of the time in the background in a window to monitor) to see if there's any correlation.

How many signal bars are you getting?  And can you get your signal bars to change by merely moving the laptop a few inches?  If the latter is the case you'll likely to have random problems especially if your signal strength goes down very low.

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## Holysword

 *eccerr0r wrote:*   

> Ethernet is the easiest way to tell if it's your ISP's fault.  
> 
> Also the closer you are to your AP the less likely you'll have a problem with interference.  You can also run ping against your AP during the time you have problems (or you can keep it running all of the time in the background in a window to monitor) to see if there's any correlation.
> 
> How many signal bars are you getting?  And can you get your signal bars to change by merely moving the laptop a few inches?  If the latter is the case you'll likely to have random problems especially if your signal strength goes down very low.

 

I am actually on ethernet cable right now. It still drops every now and then. Much less often than wireless but still seem to drop.

The router is literally 20cm away from my laptop, which is open.

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## eccerr0r

Ouch.  Time to complain to your ISP :(

You should still do the ping test over wifi (and make sure your router will respond to pings), just keep an xterm in the background pinging your AP/router.  Then you can see if you see any packet loss through the airwaves.

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## Holysword

 *eccerr0r wrote:*   

> Ouch.  Time to complain to your ISP 
> 
> You should still do the ping test over wifi (and make sure your router will respond to pings), just keep an xterm in the background pinging your AP/router.  Then you can see if you see any packet loss through the airwaves.

 

That is indeed a simple test. I'll give it a try.

I remember having a bug several years ago with the driver where it couldn't "keep alive" the TCP connection, and it was purely configuration. There was a bug somewhere which would make packets to be sent rather randomly, so the remote server would sometimes not receive them on time and therefore disconnect. That was many years ago though, and in a completely different machine! I wonder if this problem now could be any related - specially since I found this bug report associated with N-1000.

I will test the ping thing with my router. If the router responds, then it is between the router and the ISP. I'll post the results!

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## Holysword

Is there any way to pipe ping's output to a loop in bash? Something like

```
while read -r CURRENT_LINE

do

       Do Stuff

done < ./"$MYFILE"
```

but instead of reading from a file, reading from ping output. I tired dumping ping's output to a file and then reading from the file, but then I have to put it to run in the background and I always end up with an orphan ping process running somewhere when I terminate the bash script.

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## Holysword

```
(...)

64 bytes from 192.168.0.1: icmp_seq=1329 ttl=64 time=4.91 ms

64 bytes from 192.168.0.1: icmp_seq=1330 ttl=64 time=5.03 ms

64 bytes from 192.168.0.1: icmp_seq=1331 ttl=64 time=5.11 ms

64 bytes from 192.168.0.1: icmp_seq=1332 ttl=64 time=4.77 ms

64 bytes from 192.168.0.1: icmp_seq=1333 ttl=64 time=4.70 ms

64 bytes from 192.168.0.1: icmp_seq=1334 ttl=64 time=4.71 ms

64 bytes from 192.168.0.1: icmp_seq=1335 ttl=64 time=4.80 ms

64 bytes from 192.168.0.1: icmp_seq=1336 ttl=64 time=4.47 ms

64 bytes from 192.168.0.1: icmp_seq=1337 ttl=64 time=4.66 ms

64 bytes from 192.168.0.1: icmp_seq=1338 ttl=64 time=4.75 ms

64 bytes from 192.168.0.1: icmp_seq=1339 ttl=64 time=4.58 ms

64 bytes from 192.168.0.1: icmp_seq=1340 ttl=64 time=4.99 ms

64 bytes from 192.168.0.1: icmp_seq=1341 ttl=64 time=5.38 ms

64 bytes from 192.168.0.1: icmp_seq=1342 ttl=64 time=4.48 ms

64 bytes from 192.168.0.1: icmp_seq=1343 ttl=64 time=4.98 ms

64 bytes from 192.168.0.1: icmp_seq=1344 ttl=64 time=4.82 ms

64 bytes from 192.168.0.1: icmp_seq=1345 ttl=64 time=8.32 ms

64 bytes from 192.168.0.1: icmp_seq=1346 ttl=64 time=21880 ms

64 bytes from 192.168.0.1: icmp_seq=1347 ttl=64 time=20882 ms

64 bytes from 192.168.0.1: icmp_seq=1348 ttl=64 time=19884 ms

64 bytes from 192.168.0.1: icmp_seq=1349 ttl=64 time=18886 ms

64 bytes from 192.168.0.1: icmp_seq=1350 ttl=64 time=17889 ms

64 bytes from 192.168.0.1: icmp_seq=1351 ttl=64 time=16891 ms

64 bytes from 192.168.0.1: icmp_seq=1352 ttl=64 time=15893 ms

64 bytes from 192.168.0.1: icmp_seq=1353 ttl=64 time=15137 ms

64 bytes from 192.168.0.1: icmp_seq=1354 ttl=64 time=14140 ms

64 bytes from 192.168.0.1: icmp_seq=1367 ttl=64 time=1221 ms

64 bytes from 192.168.0.1: icmp_seq=1368 ttl=64 time=224 ms

64 bytes from 192.168.0.1: icmp_seq=1369 ttl=64 time=14.3 ms

64 bytes from 192.168.0.1: icmp_seq=1370 ttl=64 time=13.9 ms

64 bytes from 192.168.0.1: icmp_seq=1371 ttl=64 time=17.1 ms

64 bytes from 192.168.0.1: icmp_seq=1372 ttl=64 time=17.2 ms
```

I would definitely say that the communication between my router and my laptop stop working at some point. At this point, it could be a problem with the router or with my board, is that right?

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## eccerr0r

You can tee it: 

ping host | tee logfile.txt

But I think you just need to look at it when you're having issues, that should be enough:)

But yes it looks like you also have client to AP problems...  At least it is trying to make sure you don't lose packets.

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## Logicien

I ever had an Intel Centrino wireless card, but not your model. You can pass some options to the iwlwifi module that may help to drop less packets. You will have to test each relevant option one by one and in combination with others. See the output of

```
modinfo -p iwlwifi
```

and create file /etc/modprobe.d/iwlwifi.conf and put your options for the module in. Disable the 11n functionnality can help.

I assume that iwlwifi is compile as a module, what is better from experiences I have seen. Be sure too, that the powersaving mode of your wireless card is off before doing any test.

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## Holysword

 *Logicien wrote:*   

> I ever had an Intel Centrino wireless card, but not your model. You can pass some options to the iwlwifi module that may help to drop less packets. You will have to test each relevant option one by one and in combination with others. See the output of
> 
> ```
> modinfo -p iwlwifi
> ```
> ...

 

Thank you for your comment. I will test that asap. For the moment I can tell about another test I have done.

Two laptops, one connected throught ethernet cable, another with wireless. Both are set to ping, and both are very close to the router.

The connection problem happens with both computers at the same time. The wired connection simply takes a very long time to receive the ping response. The wireless computer loses its connection, and then reconnects again at the same time that the wired connection receives the ping response.

If iwlwifi is used exclusively for wireless and not for wired connection, then we cannot really blame iwlwifi. Also, I`ve tried the wireless laptop with my own configuration/flags/kernel (which could be innapropriate) AND I have just tried with SystemRescue CD. Both present exactly the same behaviour.

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## eccerr0r

Maybe it's your AP/router now?  That it sometimes hiccups on both Ethernet and wifi?

Curious as to who made the router, is it the Netgear N-1000?

I recall Netgear running some of their hardware too hot and causing problems occasionally.  Though I would have thought they should have gotten their act together on overheating, who knows...

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## Holysword

 *eccerr0r wrote:*   

> Maybe it's your AP/router now?  That it sometimes hiccups on both Ethernet and wifi?
> 
> Curious as to who made the router, is it the Netgear N-1000?
> 
> I recall Netgear running some of their hardware too hot and causing problems occasionally.  Though I would have thought they should have gotten their act together on overheating, who knows...

 

Now that you mentioned... it was not hot, but it did have some vents semi-blocked. I let it there because it was not overheating anyway. It is a Cisco router (those given for free by the ISP when you sign the contract).

I moved it somewhere else, and now the connection seems far more stable and my ping has improved dramatically. And now it is sort of overheating. Go figure out...

Well, I'll mark this as solved for the moment. Thanks everybody.

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