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New Member

Port failure 6509

I suddenly lost communication between server and cat 6509 (catos) switch.

Nothing on the switch indicated failure.

I ran show port 9/13 and it showed as connected. Interface on the server was up. I could see TX number on a switch going up but not RX. What is even more weird is when I ran tcpdump on the server, i saw CDP info going to the server, but notghing else. Usually i see other stuff like spanning tree messages or HSRP.

I then plugged in the server to the other switch port using the same GBIC, the same cable and it worked. So it had to be port on a switch that failed. Any ideas why the port did not show as down?

How can i further troubleshoot what went wrong?

New Member

Re: Port failure 6509

Check the duplex settings on the switch and the server.


Re: Port failure 6509

Its possible the port got into a stuck condition which is usually a code issue. Did you at the very least try to reload the slot ?

Re: Port failure 6509

When the device connected on one port stops communicating and it starts talking and connecting after it was moved to another port the switch is usually blamed since the device started to work on another port. However, when you disconnect that device/host it is equivalent to bouncing the port. Have you tried bouncing the original port? If you put it back in original port it would probably work. You stated that the port is transmitting but not receiving, switch usually does not control the RX end. It can alos be due to asic issue, have you checked the asic register's errcounters? I can send you a command to check those but I need to know what kind of line card. Then finally, as last resort to find true root cuase is to sniff the port, it's simple to sniff it by simply pinging from a device in the same subnet as that device, you should see confirm whether the switch is sending the packet and if the device is actually responding. If the switch is sending and the device is not responding, it would be hard to argue that it's a switch issue.

Hope that helps in the future.

New Member

Re: Port failure 6509

OK guys (and girls) here is some more info

The line card is WS-X6416-GBIC Switch runs CatOS.

I Plugged in my laptop to that port and sniffed the traffic. My laptop was able to receive CDP info from the switch.

I also run show cam dynamic 9/13 and the MAC was not in the table which means that my notebook cannot send information to the switch.

I checked counters on the port ( show counters 9/13 and can see rxTotalDrops = 44000

Other ports on the line card seem to be fine.

Please send me some other commands that could help me in finding root cause of the problem.

I am not sure if this is a problem with the port alone or a whole card, or a software.

Also the Hw version of that line card is 1.2

Thanks a lot for your help

Re: Port failure 6509

show asicreg 9/13 pinnacle errcounters - this gets reset on read. Obviously the port have to be connected for this command to give you meaningful output.

show mac 9/13 will give you the port tx/rx counters.

Check to see if dynamic cam entries are being created for any traffic entering the port you are trouble shooting. Make sure that the cam entry is associated with the correct vlan.

sho cam dynamic 9/13

Check for any port related error messages in the log via “show logging buff 1023”.

Make sure that the port in question is forwarding for spanning tree on the correct vlan. Make sure that portfast is enabled or disabled where appropriate.

show spantree 9/13

New Member

Re: Port failure 6509

after i reset the line card. the port started to work.

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