PC can't connect to cisco switch, "identyfing" to "unplugged"

[bob13337]

Hello I have a Cisco IE3400H. For some reason when I plug my PC in you'll see it try to connect, then it disconnects. It just keeps spamming between "Identifying" to "Unplugged". I have another PC and that one connects just fine with the same exact IP address Setup. What would cause the Cisco to not allow a PC to connect to it? It doesn't even blink green acknowledging it sees a device plugged into it on the cisco side.

This is all done connecting directly to it not wifi.. I have setup 20 switches on this job and for some reason my main pc i like to use won't allow me to connect to any cisco switches in this plant. I can connect to any other device.

[Flavio Miranda]

Hi @bob13337 

 On explanation could be the PC that does not connect is trying to get dhcp from the network and it is failing. Whilst the other PC have static IP configured.

[bob13337]

The Cisco switch has an IP of 120.15.209.20.. both PC's are setup to 120.15.209.253... obviously not connecting at the same time. subnet 255.255.255.0

[Flavio Miranda]

Can you share the switch´s config?

[bob13337]

Will be a few need to grab other computer.. The switch is running and all devices / data is communicating. PLC can see all devices through cisco switch so I know setup should be alright. GM plant and its running on over 20 cells in auto atm. Just annoyed my main PC cant access switch.

[Flavio Miranda · Accepted solution]

Make sure the port is set to non-negociate and your PC is in an different interface speed.

[bob13337 · Accepted solution]

Issue had to due with speed. Even though both computers have a 2.5 gigabit Ethernet adapter and both set to auto negotiation for some reason it doesn't work on my main pc. Changed speed to 100mps full duplex and could connect.

[Flavio Miranda]

Good.   My last log was actually talking about it.