LAN network identified on all systems, except one.

[trio3d]

Hi,

I have two networks at work,
Public - for accessing internet and
Private - non internet, static IP for accessing internal devices.

For some reason the when the private LAN cable is hooked into my work laptop, it is not detected at all (the up link/down link lights don't blink or the network icon on task bar), but it works on all other laptops in the office. I know it's not IP because my connection is not recognized as if there is no cable connected (or No network listed).
There is no issue when I hook my laptop to any other LANs.

So, I ruled out
Cable issues - the cable tester worked well, other laptops work fine on the cable.
IP conflicts
LAN port on my laptop - because other connection work very fine

I'm speculating on MAC ID blocking.
Could that be a reason? What else could cause this?

 

[bill001g]

These are very tough to find unless you have access to both ends of the connection. If you get lights at all even if they don't blink it generally means you have a good connection to the switch. It means at a very basic electrical level the PC and the switch have negotiated things like speed and duplex.

Once you get past this point and it doesn't work you really need to be able to log into a switch and see what it doesn't like. Could be anything from the mac id block as you suspect but it can be lots of things like spanning tree or a port configured as tagged etc etc.

Since you say it must be set with static IP I would verify that you have your subnet mask correct and the default gateway correct. You can run wireshark and see if you are getting any traffic at all. You should always see some small amount of broadcast traffic. If your machine sends traffic (you should see arps for the gateway) but gets no response it almost has to be something with the switch. Then again if it is a non managed switch then it must be something else.

 

[trio3d]

The switch is a remotely managed one. It's confusing why all other PCs can access the network except mine.
I don't think it's the ethernet port of my laptop because it works on other networks.

I tried wireshark, and there is no traffic at all.

 

[bill001g]

You should at least see DHCP requests from your machine. You may have to force a ipconfig/renew to get it to try again. Still normally you see some random broadcast from the switch and when you do not see this it implies there is a issue with the switch.

I know commercial cisco switches can get the ports in a funny err-disabled state that unless you happen to see one little status line they look fine but just don't work.

I would see if you can gain access to the switch and see the status of that port. You could also try to plug into a different port on the switch you know functions with another PC.