erber
Posts: 2
Joined: Mon Jan 06, 2014 12:33 pm

Connecting to internet via cable and router

Mon Jan 06, 2014 1:02 pm

New on this, so be patient.

Connected my RPI direct to the router via cable. Works ok and no problem at all.

Then I moved the RPI to another room and connected the the RPI internet cable to a internet wall socket. But it dosent work. :?: That socket is connected to the SAME router via cabel "permanently mounted" in the wall.

Dont know exactly the english words for it. Tried to ping the router and outside, but there is no IP address. Tried IP A and so on.

As long as I understand there should not be any issue with the cables. The only diffrent betweend the two is that wall cabel and the socket when connecting to the router.

I know the internet wall socket works just fine, since WIN computers can connect to network and internet without any problems.

Can anyone shed some light on this problem, I tear my hair out of frustration. :D

Erber
/Sweden

obcd
Posts: 917
Joined: Sun Jul 29, 2012 9:06 pm

Re: Connecting to internet via cable and router

Mon Jan 06, 2014 1:51 pm

It could still be the cable and the wall socket. Most network adapter have an option to swith to 10Mbit speed if 100Mbit isn't working. At 10Mbit, only 2 pair = 4 wire of the 8 are used. For 100Mbit, you need all 4 pair if I remember well. I have no idea if the Pi would work when only 2 pair of the network cable are functional. Some routers have light indicators that show if a connection is 10 or 100Mbit. This could give an indication of such a problem.

Khaled.M
Posts: 8
Joined: Sat Oct 19, 2013 1:26 pm

Re: Connecting to internet via cable and router

Mon Jan 06, 2014 1:55 pm

Well, if you are saying that the same RPI works with the same router directly but not from the socket, and the same socket works with other Windows PC, then I would say it is the attenuation from extra splices and terminations. In basic English, the RPI does not give out enough power on the line to reach the router.

Just like I remember on one thread that one guy was using a long HDMI cable with certain device connected to TV and was working but did not work with RPI, a shorter HDMI cable worked.

Edit: for the above reply, both 10Mbps and 100Mbps (Eth and FE) use 2 pairs, it is 1000Mbps (GbE) that uses 4 pairs.

User avatar
Richard-TX
Posts: 1549
Joined: Tue May 28, 2013 3:24 pm
Location: North Texas

Re: Connecting to internet via cable and router

Mon Jan 06, 2014 1:59 pm

Try forcing the Pi to use 10Mbit. Also try half duplex.

http://www.raspberrypi.org/phpBB3/viewt ... 66&t=45788
Richard
Doing Unix since 1985.
The 9-25-2013 image of Wheezy can be found at:
http://downloads.raspberrypi.org/raspbian/images/raspbian-2013-09-27/2013-09-25-wheezy-raspbian.zip

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rpdom
Posts: 16363
Joined: Sun May 06, 2012 5:17 am
Location: Chelmsford, Essex, UK

Re: Connecting to internet via cable and router

Mon Jan 06, 2014 2:21 pm

obcd wrote:It could still be the cable and the wall socket. Most network adapter have an option to swith to 10Mbit speed if 100Mbit isn't working. At 10Mbit, only 2 pair = 4 wire of the 8 are used. For 100Mbit, you need all 4 pair if I remember well. I have no idea if the Pi would work when only 2 pair of the network cable are functional. Some routers have light indicators that show if a connection is 10 or 100Mbit. This could give an indication of such a problem.
Actually both 10Mbit and 100Mbit only use 4 wires (2 pair). It is 1000Mbit that needs all 8 wires (4 pair).

It still sounds like a cable/socket problem though.
Last edited by rpdom on Mon Jan 06, 2014 3:44 pm, edited 1 time in total.

erber
Posts: 2
Joined: Mon Jan 06, 2014 12:33 pm

Re: Connecting to internet via cable and router

Mon Jan 06, 2014 3:04 pm

But what can be the problem with the cable or the socket? I've tried it and it works just fine - with Window based machines. It has worked for 3 years.

I've also changed the cable from the socket to RPI, and it's the same result.

Tried also to have one power to the RPI (1A) and one for the USB-hub. Same result.

Many thxs for every suggestion. :)

Khaled.M
Posts: 8
Joined: Sat Oct 19, 2013 1:26 pm

Re: Connecting to internet via cable and router

Tue Jan 07, 2014 7:05 am

erber wrote:But what can be the problem with the cable or the socket? I've tried it and it works just fine - with Window based machines. It has worked for 3 years.

I've also changed the cable from the socket to RPI, and it's the same result.

Tried also to have one power to the RPI (1A) and one for the USB-hub. Same result.

Many thxs for every suggestion. :)
So right now if you connect your PC to that socket it works? and you unplug the cable from PC and use the same cable to connect RPI it doesn't work? sounds like power issue on the Ethernet port itself as I said on the previous post, as when you connect directly the PI to the router you have only 2 termination (splicing) points on both ends of the cable, through the socket (I assume the setup is like this Router <--> Patch Panel <---> wall socket <---> RPI) you have 6 termination points (4 more than previous) and each of these puts extra attenuation (signal/power drop on the line).

obcd
Posts: 917
Joined: Sun Jul 29, 2012 9:06 pm

Re: Connecting to internet via cable and router

Tue Jan 07, 2014 9:28 am

Try to connect an ethernet switch to the wall socket and connect the Pi to that switch.
If the problem is 2 much attenuation of the ethernet signals, that should fix the issue.
I once serviced some bad wiring connection. An old pc with 10Mbit adapter could connect fine. A newer one with a 100Mbit adapter refused to connect. That's what got me confused with the number of used wires. So, forcing 10Mbit and half duplex might be an interesting test as well.

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