Issues splitting Ethernet port


I'm having some issues sharing an Ethernet data port RJ45.

My setup is like this: in the basement of our building is the switch distributing to all the different ports in the building.

At one of the ports, I would like to share the connection between several computers. For this purpose I have bought (several) Network switches, eg TP LINK, however, when nothing happens - connecting from ethernet port to ethernet switch is fine, but when I connect computers to the switch, i get no line.

Any ideas what this can because of?

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Going to have to tell more.

Somewhere in your setup you need a router if you are to share an Internet connection. A switch is used for building a network, not usually what folk want when they want to share an Internet connection. That is:

Internet -> ROUTER -> then to the switch(es).

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More info

Yes sorry, we have a router.

We have fiber connection in the building.

So we have the line in that connects to a router -> fire wall -> switch -> patch bay -> individual RJ-45 ethernet outputs

I'm trying to connect an extra ethernet switch to the ethernet outputs to share the connection.

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Topography and cabling

make sure your switches are auto mdix or use crossover cables if not. Make sure you have no loop-backs from switch to switch. Your router's switch ports can only handle one other device each. If you've more switches than router ports, you'll need may need to daisy chain the surplus switches.

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Hi, thanks for the answer.

I'm not sure I 100 % follow - you say that I can't connect a small ethernet switch to the RJ45 port to split the connection?

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Not what I meant to infer

You said you had a router and several switches. Your router (no model given) may or may not have more than one switch port. Many have 4/5 ports and most (but not all) are auto mdix which means they can determine whether ports are up/down link and adjust as necessary. Otherwise, you may need to use crossover cabling in specific locations or push a button on the switch if using a dedicated uplink port. Again, switch models were not given and some have such ports but they might be shared. Shared ports become an "either/or" function but that's another topic. You didn't mention much about topography other than device to device but there are some things that can be observed. You said that connecting computers to a switch gets you no line and, since you mentioned a "patch bay" (presuming you meant patch panel) I'll guess you're using a direct connection to the switch rather than a port at a remote termination point. Those termination points should be wired to the patch panel. If all wiring is good, attaching a PC at a termination point should light an LED on the switch to which it's electrically connected. No LED means no physical connection. Is that what you're seeing or is it just that you have no network connection that provides an IP address to the PC? You also mentioned a firewall between the router and switch. That's another variable that needs to be considered and possibly bypassed as a test in the event a physical connection is confirmed.

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Thank you for taking the time and your full answer!

I can see my explanation is a bit vague - possibly due to my lack of technical knowledge. I will try and upload a couple of pictures, maybe it will clarify some things

So, this is an image of the switch. Connecting to the switch below (not shown is the fire wall and the router with the fiber connection).

The switch is then connected to the patch bay:

The patch bay connections are then distributed out in the entire house / office and each out put looks like this:

This is also what I refer to as 'data ports'.

What i'm trying to do is share a single data port between several computers. To do this, I'm trying to connect and extra Ethernet switch directly to the data port. Which looks like this:

However, when I connect (the line works, full connection if I plug in directly to a computer), then nothing happens with the ethernet switch and there is no connection. It flashes, but that's all.

Is it not possible to divide one data port like this? Can there be issues with the actual network switch, firewall or ip addresses?

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Thanks for the images but, IMO,

it would take an on-site person with good troubleshooting equipment and knowledge to sort out your problem. All is see is what looks like a variety of hardware that has been added over time and...sorry to say...looks very messy. It appears to have hardware from your ISP and of your own. My only experience outside of my own home was wiring and maintaining a network cabinet for a school which also has a similar mixture of hardware to what you show but I've keep it as neat and simple as possible. I'm just a volunteer there but that system has been relatively trouble free.

I see you have at least one Cisco device, some D-link hardware, etc. Your "data port" appears to be a simple tplink 5 port 10/100 switch so I'm not certain where it fits into your overall topography. About all I can suggest at this point is that you consider getting an on-site visit by a qualified networking specialist to assist you. Someone needs to put their eyes on this. Best of luck to you.

Post was last edited on November 19, 2019 9:09 AM PST

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use any ports but 1 and 5 on that switch, use 2&3 of the switch, one of the ports you are using is set up as an uplink port and will not switch the other ports.

If the building's dhcp server doesn't assign you extra ip address, use a router and connect the wan to the building's network, and of course the Ethernet to your computers.

Post was last edited on November 21, 2019 9:50 AM PST

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Which port should I use for the connection line in then? And I can use the remaining ports to distribute the connection out?

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use a non uplink port

I would try 2 in, 3 out, one of those ports (1 or 5) you can't use other than daisy chaining other switches, which is usually labelled "uplink". The switch doesn't care which port the downstream cable (to the internet) is plugged in, except the uplink port.

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