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Posted By: Keyset6 Identifying a connected network cable - 07/17/20 07:32 PM
Wasn't sure which forum to post this in. Had a customer who's downsizing that wanted to disconnect phone and data connections in a vacated part of the building. As suspected, most of the data jacks weren't labelled on the patch panel. When toning a cable connected to a PBX line, if a phone couldn't be plugged in to identify the line/port due to it being defective or deactivated I'd use an open pair to be able to hear the tone better. I've had success with hearing a tone on a cable connected to a PBX port, difficult but listening very carefully is not impossible. With a network port though, it brought the tone down to nothing on a given pair. I then put the tone on pins 1 & 4 I believe, the test tone seemed to be a bit less muted not being on a dedicated pair. Still lucky to hear it at all though. Found that, 2 others I ended up by trial & error unplugging network ports that were inactive, a few at a time until the jack was dead. A lot of walking back & forth, sure would have been easier with 2 people to watch network port lights on a device.

The network cable tester I went and got from a co-worker wouldn't power on, maybe the battery was good enough for my basic telco tone generator but not the tester. Still, probably the tone would just be just a bit stronger anyway. I'm an old school T&R guy, but these days of course involved with networking in a basic form at least with VoIP. I've used a cable tester after connecting plugs and jacks plenty of times, but Is there a device that could plug into a network jack that would ID the port that it's on? Or - some kind of utility on the switch/router that would indicate which port a test device is plugged into, or simply an app for a PC that could indicate the port it's on? Or - something like the intercoms from years ago that would use the house AC wiring to transport audio, maybe it was a carrier signal that rode on the AC wiring. Makes me think of an old 'Carrier Current' AM radio station on a college campus.There's got to be an easier way than what I did today.
Regarding the Network port the easiest way requires two people.

One person connects a device into the data location you want to remove.
The second person monitors the network.
Person out on the floor plugs in the data cable for 3 seconds, unplugs it for 3 seconds and repeats.
Person in the data closet look for the blinking connectivity light.

For a single person. Make a note of which ports on the switch are active.
Plug in a device out on the floor location.
Compare your list against what ports are now showing connectivity.

For active network ports A different tester can help such as a Fluke IntelliTone Pro LAN Tone/Tester. "Digital network cable toner and probe traces and locates cables on active network."

https://www.flukenetworks.com/datacom-cabling/copper-testing/IntelliTone-Pro-Toner-and-Probe
The Fluke IntelliTone™ Pro 200 LAN Toner, Tracer and Probe is designed to work on active network drops. I used it for years before I bought my Fluke CableIQ™ Qualification Tester which does the same thing and more.
Posted By: Keyset6 Re: Identifying a connected network cable - 07/17/20 10:30 PM
Thanks - looks like the Fluke IntelliTone Pro or something like it, is the way to go. Yea I was hoping I'd have some help with this, one watching the switches while the other plugs/unplugs a laptop at the jacks but that wasn't an option. I was about to use the 'Single Person' method.

The network and PBX 'closet' is just a narrow space behind a wall with no lighting. There's about a foot of flooring from the wall, after that it drop down about a foot. When making phone moves I stand on the floor and lean back against a metal stud, with a flashlight. I check out the Fluke IntelliTone Pro some more.

If I had networking knowledge and access to the customer's switch - after obtaining an IP address via DHCP I'd run a command (assuming there is one) to see which port that particular IP address is on.
Posted By: EV607797 Re: Identifying a connected network cable - 07/20/20 05:42 AM
Keep in mind that many network switches are POE, meaning that power is provided over the full (shorted together) white/blue and white/brown pairs. Even non-POE switches have these pairs shorted, hence the reason why traditional telephone type toners go dead. You'll be driving yourself crazy trying to tone split pairs as you mentioned since you tone will be 'wild', or bleeding through all over the place.

The white/orange and white/green pairs are still isolated from all others, so your best bet is to use a 'banjo' and send your tone over the white/green pair. Your biggest obstacle is that getting a tone to be traceable via ANY pair through CAT5 and above is a challenge. That's the reason that they made these cables; so that signals DON'T leak out of the cable. Still, the second or third pairs are your best shot at picking up anything with a tone tracer.

The first and fourth pairs being shorted isn't always a bad thing. At least that tells you that it's plugged into a port on the switch, but that's of little importance to you right now.

Dean's method of having someone to watch the status LEDs on the switch is the most fail-safe way to do it, but having a second set of eyes is a luxury these days. Still, the other method of running back and forth will be the second-most reliable method. It sounds as if this is what you're trying to avoid.
Posted By: metelcom Re: Identifying a connected network cable - 07/20/20 11:12 AM
Pockethernet is the device that you need.
Try this old-school method for toning voice pairs, or data pairs that are not connected to the switch:

Put one clip of the toner on a single conductor (or a shorted pair) in the cable. Put the other clip on ground.

Use an Aines orange toner. They're the best.

By the way, did you ever notice when trying to locate a pair with a very weak signal, that if you're outdoors, a guy will start up a leaf blower, or if you're indoors, someone will start a vacuum cleaner? I believe that there is an evil genius who monitors our every move, and sends out a gardener or a custodian whenever he detects us putting a toner on a pair. It's not just paranoia...
Posted By: Ruben Re: Identifying a connected network cable - 07/20/20 07:06 PM
I have a extensive home network and for running down cables and faults I use:
Okay don't pick on me guys.
But for a low cost cable id tool and quick diagnostics.
I use the klein scout pro 2.
Current version is the scout pro 3. which has more features for the same price.
It works extremely well with the mapping terminators for me as well as testing open,shorted and mismatched pairs and length of cable
They both have a tone generator but you need to buy a compatible sensor.


On the scout 3 the hub feature causes the led's on the switch,router to blink.
They both are not recommended to use on POE
Plus it has back lighting and multiple tones.
Plus you can get length by pairs for finding a broken cable.
And it is rated for cat 7 and will show it as shielded.

There are ton's of accessories for both.
Like extra mapping terminators all with unique ID's
Posted By: hbiss Re: Identifying a connected network cable - 07/20/20 09:17 PM
Quote
If I had networking knowledge and access to the customer's switch - after obtaining an IP address via DHCP I'd run a command (assuming there is one) to see which port that particular IP address is on.

If you had networking knowledge you would know that there is no such thing. frown

-Hal
Posted By: jeffmoss26 Re: Identifying a connected network cable - 07/20/20 09:52 PM
Hal, if you had a Cisco switch with port security which restricts a physical port to one MAC address, it would be possible.
Posted By: hbiss Re: Identifying a connected network cable - 07/21/20 05:11 PM
Yeah, but wouldn't you have to set that port up first? Isn't going to help you if you just plug an unknown PC into an unknown jack. PC wouldn't even connect, right?

-Hal
Posted By: metelcom Re: Identifying a connected network cable - 07/22/20 12:14 PM
You can identify a switch connection by using LLDP on most switches and if it's a Cisco CDP will give you info about the port connection. The Pockethernet does both. You can also find software for laptop that will do this but much easier with the Pockethernet.
how about "show arp" on the switch - you get a list of ports, the IP address associated with it, and the MAC address
Posted By: jeffmoss26 Re: Identifying a connected network cable - 07/22/20 10:04 PM
don't think ARP would show physical ports. It just corresponds IP to MAC
Code

AAA Switch B>enable
AAA Switch B#show arp
===============================================================================
                              IP ARP
===============================================================================
IP Address      Age (min) MAC Address       VLAN-Unit/Port/Trunk Flags

-------------------------------------------------------------------------------
192.168.43.15   0         b4:47:5e:f0:a0:41 VLAN#2               L
192.168.43.255  0         ff:ff:ff:ff:ff:ff VLAN#2               LB
192.168.1.255   0         ff:ff:ff:ff:ff:ff VLAN#1               LB
192.168.1.31    56        24:be:05:03:3d:b3 VLAN#1-4             D
192.168.1.47    16        24:be:05:07:7f:87 VLAN#1-5             D
192.168.1.198   81        00:80:91:b1:fe:73 VLAN#1-24            D
192.168.1.30    59        8c:ec:4b:a3:1b:1e VLAN#1-15            D
192.168.1.125   0         b4:47:5e:f0:a0:40 VLAN#1               L
192.168.1.253   319       a4:2b:b0:f1:aa:3c VLAN#1-24            D
192.168.43.13   276       00:0c:29:dd:37:9f VLAN#2-23            D
192.168.1.141   185       00:0c:29:26:9a:77 VLAN#1-23            D
192.168.1.205   35        00:80:91:b2:f0:8a VLAN#1-23            D
192.168.1.53    33        74:46:a0:c1:fc:ca VLAN#1-23            D
192.168.1.20    189       00:1d:09:81:8f:a2 VLAN#1-23            D
192.168.1.36    97        d4:ae:52:7d:6f:7e VLAN#1-23            D
192.168.1.52    8         e4:54:e8:be:7c:af VLAN#1-11            D
192.168.1.123   359       00:0c:29:dd:37:95 VLAN#1-23            D
192.168.1.203   99        88:51:fb:ea:63:37 VLAN#1-9             D
192.168.1.19    85        a8:5e:45:56:84:15 VLAN#1-23            D
192.168.1.90    87        4c:11:bf:44:1b:f8 VLAN#1-23            D
192.168.1.42    82        24:be:05:03:3d:d5 VLAN#1-8             D
192.168.43.10   68        00:e0:07:8b:4b:b2 VLAN#2-23            D
192.168.1.18    13        08:2e:5f:02:5b:f0 VLAN#1-23            D
192.168.1.89    198       38:af:29:89:3f:3e VLAN#1-19            D
192.168.1.33    195       2c:41:38:b9:9b:ca VLAN#1-24            D
192.168.1.249   179       00:80:91:76:60:56 VLAN#1-13            D
192.168.1.9     171       8c:ec:4b:6a:fa:98 VLAN#1-23            D
192.168.1.1     85        2c:b8:ed:5d:23:80 VLAN#1-23            D
192.168.43.0    0         ff:ff:ff:ff:ff:ff VLAN#2               LB
192.168.1.0     0         ff:ff:ff:ff:ff:ff VLAN#1               LB
192.168.1.8     299       e4:54:e8:bc:2f:3f VLAN#1-23            D
192.168.1.208   121       b4:b5:2f:f6:f5:7b VLAN#1-23            D
192.168.1.32    42        8c:ec:4b:a2:e8:92 VLAN#1-2             D
192.168.1.56    23        90:b1:1c:5f:d5:de VLAN#1-7             D
Total ARP entries : 34
-------------------------------------------------------------------------------
Flags Legend:
S=Static, D=Dynamic, L=Local, B=Broadcast
AAA Switch B#
Remember the original issue:

"a customer who's downsizing that wanted to disconnect phone and data connections in a vacated part of the building"

Active ports plugged into vacant locations and his standard Tone Generator and Inductive Amplifier isn't working for him.
Posted By: hbiss Re: Identifying a connected network cable - 07/23/20 04:14 PM
Originally Posted by Professor Shadow
Remember the original issue:

"a customer who's downsizing that wanted to disconnect phone and data connections in a vacated part of the building"

Active ports plugged into vacant locations and his standard Tone Generator and Inductive Amplifier isn't working for him.

What I would do is tag and disconnect all dark drops from a switch then put tone on a vacant jack(s) (if you have more than one toner that would really speed things up). Then find the drops back at the switch with your probe.

If your toner/probe can't work with unterminated CAT5 you need a better one! The probes with the insulated tips are junk.

What I've done also is to use my STM-8 cable mapper with several remotes plugged into several jacks. Just take the drops at the switch and connect them to the mapper one by one. When it shows a remote you found a jack.

Easy peasy.

-Hal
Posted By: metelcom Re: Identifying a connected network cable - 07/23/20 08:15 PM
I think my way is easier than that. I plug cable into Pockethernet, open the app on my phone and connect to device, run test. This will give me POE info, all 4 pair + shield length and status, Link speed, switch info with switch ID and port # you're connected to and more if I wanted it. This saves me a lot of walking many times I don't even have to locate the switch.
Posted By: hbiss Re: Identifying a connected network cable - 07/24/20 04:21 AM
I was suggesting ways to do it with equipment that he should already have. Certainly if he wanted to buy some new gear the Pockethernet sounds like a great addition.

-Hal
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