Help find unconnected cables 1

[franklin97355]

Here is my problem. I have thousands of jacks that may or may not have a computer with an ethernet card attached. Now, the ones that have a computer with WOL will in most cases have a link light at the switch. My question is, is there a way to tell if there is a card attached to a port if the computer is turned off and not powered? (magnetics, caps, resistors, etc.) that would allow me to remove jumpers and recover switch ports? I could probably build a small circuit if I knew there was a way and what to look for.

Thanks, Steve

 

[jimbopalmer]

I confess I do not use your technique, I use managed switches, when I suspect I have 'too many' unused ports I clear statistics and check again in 2 weeks. The ports that have 0 statistics in two weeks get unplugged.

If you do not have managed switches, I suggest 10 AM and 2 PM to check for blinky lights.

another approach might be to use the angry IP scanner to find out what does exist, but I bet that is messy.

I tried to remain child-like, all I acheived was childish.

 

[edfair]

An ohm-meter should indicate some resistance on the transmit pair if there is a computer connected.
I suspect that a battery and a led would work but it may take some experimentation.


Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[franklin97355]

DOH! Ed you're spot on and why I didn't think of researching this further is all my fault. Both the TX and RCV pairs have significant resistance even if the card is not in a computer (at least the 3com and Intel cards I tested did) So, no card no loop, card < 50 ohms.

Thanks.

The answer has always been 42