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LAN Switching issue

I am having an issue that has me stupefied.

I have a 4506 of which I just upgraded to WS-X4248-RJ45V. All the PCs on this switch are working fine except two(FA3/20 & fa5/47) . I have checked Layer 1, and the wiring is not suspect. I disconnected the LAN cable from the 1ST PC (FA3/20) and connected it to my laptop and I connect at Layer 1, I get an IP address, and everything worked properly. I reconnected the LAN cable to the PC and I don?t even get a link light. At this point I am thinking that the PC is suspect and the Switch/Blade is in the clear.

Unfortunately I find out that there is another PC attached to a different blade int the same switch experiencing the same issues. I try the same thing on PC#2(FA5/46) and have the same results. Then I decide to move PC #1 to a different location and a different switch. It works fine can get on the LAN without an issues. The same thing is done with PC#2 and we get the same results.

At this point I start looking closer to my switch.

I turn off port security by removing all port security commands.

I reset the ports using the shut no shut commands.

I verify that they are on the correct Vlan.

I make sure that POE is turned off for these ports just in case it might be interfering.

I find no solution to the issue other than replacing the PC.

Also as a fallback I reinstalled one of the older WS-X4148-RJ and connected the user's laptop to a port in it and it seems to be working properly.

At this point I don't know what else to look at. I was wondering if an issue similar has been seen before. Enclosed is a copy of show Tec.

Any Help would be appreciated



Re: LAN Switching issue

I think that the port security commands has not ben cleared yet. Try clearing the interface and then clearing the mac-address-table.

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