Intermittent connection

Buenas tardes
I’m having hard time with my internet connection because it permanently connects/disconnects every few seconds even though the computer is connected with the ethernet cable and less than 1 m away from the antenna. I’m sure it is not the hardware because when I (very rarely) use windows 8 I do not have this situation.
Also, if I go to my bedroom (which is less than 3 m above) I almost loose completely the signal.
It seems to me that i need to configure “something”.
Can you help me improve my reception?
Thanks

On 2014-09-02 02:36, jazmiel wrote:
>
> Buenas tardes
> I’m having hard time with my internet connection because it permanently
> connects/disconnects every few seconds even though the computer is
> connected with the ethernet cable and less than 1 m away from the
> antenna. I’m sure it is not the hardware because when I (very rarely)
> use windows 8 I do not have this situation.
> Also, if I go to my bedroom (which is less than 3 m above) I almost
> loose completely the signal.
> It seems to me that i need to configure “something”.
> Can you help me improve my reception?

Eummm… please describe better the situation :slight_smile:

You talk on an ethernet cable, then of an antenna, then going to your
bedroom - what, with a cable from room to room? What signal can you loose?

So, I assume it is a laptop connected via WiFi which you move around.
But then where does that ethernet cable comes in? Or is it a cable to
some kind of dongle?

And if it is WiFi, people will want to know what chip, at least.


Cheers / Saludos,

Carlos E. R.
(from 13.1 x86_64 “Bottle” at Telcontar)

Hola
Thanks for answering. Yes, you’re right. Here’s the output of **/sbin/lspci (I include only the information of my wi-fi card and the Ethernet cable controller):
**


01:00.0 Network controller: Ralink corp. RT3290 Wireless 802.11n 1T/1R PCIe

08:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 07)

Allow me to explain with detail. In my library I have several machines connected to the web via an antenna. Besides, I connect them via an Ethernet cable. But sometimes I work in my living room or my dinning room or in my bedroom. So when I move around I depend only on the wireless connection. And is when I loose the signal: very low intensity and connects/disconnects.
But sometimes, even if I am less than 1 m away from the antenna AND connected with the Ethernet cable, I get an intermittent signal (comes and goes).
How could I fix this?

Well, if you really are connected via ethernet cable and have wireless connectivity simultaneously, then the wired connection will take preference. (That is a hard-wired design in NetworkManager.) So, it is not clear to me why you would experience outages when you have both interfaces active.

If you are using 802.11n connectivity, it may be that interference is causing frequent disconnections (even with good signal it is particularly susceptible.)

Is there a way to fix this issue?

As I hinted at already, if you are using 802.11n connectivity, you may need to consider disabling that for the moment. (Configure in the wireless router.)

Assuming your wireless device is enumerated as wlan0, what is reported by the following?

/usr/sbin/iw dev wlan0 link

The commands shows:


jazami:~ # /usr/sbin/iw dev wlan0 link

command failed: No such device (-19)

Thanks for your answerlol!

Your wireless device name might be different as I already mentioned.

To get that

/sbin/ifconfig

or

/usr/sbin/iw dev

then adjust the command accordingly.

/usr/sbin/iw dev <name of your device> link

I hope that is clear enough. :wink:

On 2014-09-04 00:36, jazmiel wrote:
>
> Is there a way to fix this issue?

If you say: «But sometimes, even if I am less than 1 m away from the
antenna AND connected with the Ethernet cable, I get an intermittent
signal (comes and goes).»

It means that you are connected by cable, not wireless. It takes
precedence. If connection is intermittent, cable is probably bad, so
start replacing it. If not, look at the sockets.

And, if the cable connections comes and goes, the wireless connection
will try to connect when the cable goes, and disconnect when the cable
comes back. An intermitent cable connection will cause a lot of wireless
connect/disconnect activity.


Cheers / Saludos,

Carlos E. R.
(from 13.1 x86_64 “Bottle” at Telcontar)

Yep. I totally agree. Connecting via cable simultaneously, will not help diagnose a wireless connection, and the OP wrote confusingly that the internet connection kept breaking while the ethernet cable was attached, so it reads like an ethernet connection issue, although it’s hard to tell with that ambiguous post.

/usr/sbin/iw dev <name of your device> link

Hi lol!. I did what you indicate me and here is the output when the lap is less than 1 m from the antenna and no cable connected:

$ /usr/sbin/iw dev wlo1 link
Connected to e8:94:f6:fb:c4:7d (on wlo1)
SSID: MAXCOM_C47D
freq: 2462
RX: 30315061 bytes (31160 packets)
TX: 2412791 bytes (18903 packets)
signal: -47 dBm
tx bitrate: 90.0 MBit/s MCS 4 40Mhz short GI
bss flags: short-slot-time
dtim period: 0
beacon int: 100

and this is the output when I move to my bedroom (2.5 m above the antenna):

$ /usr/sbin/iw dev wlo1 link
Connected to e8:94:f6:fb:c4:7d (on wlo1)
SSID: MAXCOM_C47D
freq: 2462
RX: 381975 bytes (2295 packets)
TX: 27864 bytes (225 packets)
signal: -78 dBm
tx bitrate: 7.2 MBit/s MCS 0 short GI
bss flags: short-slot-time
dtim period: 0
beacon int: 100

As I write this post the intensity of the signal varies wildly. (The music I’m listening is inttermitent; when I try to preview this words I have to wait the connection but sometimes is immediate…)
What causes the surprise is that if I “open” w8 I donot have connection problems and I’m sure the configuration of this distro is more sophisticated than that of windoze… but, how can I improve my connection?
I greatly appreciate and thank you guys all of your replies.:slight_smile:

signal: -47 dBm
        tx bitrate: 90.0 MBit/s MCS 4 40Mhz short GI

From your device output, I can see that the above signal is at a reasonable level, and that you are using 802.11n protocol. While this does allow for far greater throughput, what we can no easily determine (with out specialized equipment) is interference from other sources, (especially other 802.11x signals.). However, you could try a scan to see what else is around. When using a 40MHz-wide channel, there are only a very limited number of channels, and you’re bound to be impacted by other 802.11 devices.

Read below for a better understanding of this
http://en.wikipedia.org/wiki/List_of_WLAN_channels

If you have other wireless stations (devices) connected at the same time, this can also impact on QoS.

The signal level reported from your bedroom location is far weaker

signal: -78 dBm
        tx bitrate: 7.2 MBit/s MCS 0 short GI

and I would say that the devices are probably switching modulation frequently, which happens with weak signal and/or interference.

You could try changing frequency (auto to fixed channel) in the router, and/or you could try using a 20MHz-wide channel, or you could try switching to 80211b/g, (again easiest to set in the router.)

Good luck.

I really thank you all your advise. I’ll be trying to do what you suggest me to do. I’ve always found good support in this forum with high technical quality and this one is not the exception. See you next post lol!