network cable speed issue

[TechSupp]

I have one machine that started playing up with connecting to the network, as usual waggled the cables and all worked fine...or so I thought. Its now very temperamental in getting a connection and when it does it only connects a 10Mb not the usual 100Mb.

Things I have tried so far,

 

put a new network card in of a different type

Changed patch lead from PC to wall socket

Changed patch lead from patch panel to switch

Changed switch it connects to

Changed faceplate and connection socket on wall

Connected PC to another wall socket and it connects straight away at 100Mb

 

All to no avail (apart from last one)

The only thing I have not checked is the wall socket to the patch panel, not got a tester with me today.

 

If the cable has been damaged would that allow it to connect but at a lower speed or should it just not connect at all?

[Geoff]

If there is a cable fault then it will try and negotiate down to a lower speed. Another symptom would be RX/TX errors in the 'netstat -s' output or fluctuating ping times. Edited January 29, 2016 by Geoff

[TechSupp]

Thanks, I'll get my cable tester on it and see if that shows up anything.

[LytchettNM]

I would try re terminating the cabling at both the end of the suspect link making sure you cut a little off the end of each wire, I have seen many people just push down the termination tool over the top of the current termination and think that will sort it.

Have you had any work done on the patch panel / cabinet that may have disturbed the cabling?

But a good cable tester should be able to detect most of these type of fault and if you tester detects cable length comparing it to a socket next to the suspect one may help as that detects the resistance of the cable over its length so if wires inside the cable are broken you may get very different results.

[TechSupp]

Unfortunately my tester only tests continuity on each wire. Have redone the end at the wall not at the panel yet. Yes had people in, started playing up after the summer. Its not used that often and has been hit and miss with connection but when it has its been 10Mb so maybe a duff connection or broken wire.

[LytchettNM]

The tester should with a little luck find the issue!

If your structured cabling has been disturbed then I would say have a good look at that end, it's most likely a lose connection causing a high resistance with may be just one wire from that cable.

[TechSupp]

Trouble is as I only work part time people end up comming and going without me knowing! 😠

[TechSupp]

Yah, Week cant start any better, tester confirmed one of the wires was an issue, looked at back of patch panel and could see straight away which one it was. Re terminated it, tested it and PC back on fine

Now the week is all downhill from here till Friday!

[LytchettNM]

That's great news. Glad I could offer a little help.

Regards

Darren