Switch doesn't learn MAC address

[pepinpepe]

Hi,

We had a problem with a printer and to check it we connected a hub with a laptop. The hub was connected to one port 2610 procurve switch and to the hub, the printer and the laptop (to see the traffic). The port was negotiated in 10HDx mode but it was impossible to ping the printer. I could check in the mac addresses table switch for that port that it wasn't learning any mac addresses (laptop and printer) and that the entrancy was empty. I disconnected the cable and connected again but it didn't work until I connected the printer directly to the switch. I could only see ARP Requests traffic from the PC but nothing from the printer or from the network. Today I repeated all the steps and it worked. I can't understand why one day switch learns the mac and another it doesn't with the same hub and port. Does anybody what is happening? Does anybody know if there is "some circumstances" in which the switch doesn't learn mac addresses? Switches are 2610 and software release 11.25.

Best Regards.

[16again]

To capture traffic on a port, better use port mirroring feature instead of inserting a hub. 
The hub can cause additional problems (speed / duplex) so you might waste time on troubleshooting the hub connection

If some port protection mechanism kicks in , port is effectively blocked and no MAC addresses will be present.  Review switch log for events

[pepinpepe]

Hi 16again,

Thanks for your answer. There isn't any port protection mechanism, it is by default (learn mode continous). Switch Logs are almost the same the day wich I had the problem (dates are bad):

I 10/05/12 17:27:22 ports: port 13 is now off-line
I 10/05/12 17:27:33 ports: port 13 is Blocked by STP
W 10/05/12 17:27:33 ports: port 13 PD Invalid Signature indication.
I 10/05/12 17:27:35 ports: port 13 is now on-line
W 10/05/12 17:27:46 FFI: port 13-Excessive late collisions.
W 10/05/12 17:27:46 FFI: port 13-Excessive Broadcasts. See help.
W 10/05/12 17:29:31 FFI: port 13-High collision or drop rate. See help.
I 10/05/12 17:36:41 ports: port 13 is now off-line
I 10/05/12 17:36:47 ports: port 13 is Blocked by STP
I 10/05/12 17:36:50 ports: port 13 is now on-line
W 10/05/12 17:37:02 FFI: port 13 Duplex Mismatch. Reconfig port to Full Duplex.
W 10/05/12 17:37:02 FFI: port 13-Excessive late collisions.
W 10/05/12 17:37:02 FFI: port 13-Excessive Broadcasts. See help.
I 10/05/12 17:37:48 ports: port 13 is now off-line
I 10/05/12 17:38:06 ports: port 13 is Blocked by STP
W 10/05/12 17:38:06 ports: port 13 PD Invalid Signature indication.
I 10/05/12 17:38:09 ports: port 13 is now on-line
W 10/05/12 17:38:26 FFI: port 13-Excessive late collisions.
W 10/05/12 17:38:26 FFI: port 13-Excessive Broadcasts. See help.
W 10/05/12 17:40:43 FFI: port 13-High collision or drop rate. See help

as the day I did test:

I 10/12/12 19:15:01 ports: port 3 is now off-line
I 10/12/12 19:18:35 ports: port 13 is now off-line
I 10/12/12 19:19:13 ports: port 13 is Blocked by STP
I 10/12/12 19:19:16 ports: port 13 is now on-line
W 10/12/12 19:19:24 FFI: port 13 Duplex Mismatch. Reconfig port to Full Duplex.
W 10/12/12 19:19:24 FFI: port 13-Excessive late collisions.
W 10/12/12 19:19:24 FFI: port 13-Excessive Broadcasts. See help.
I 10/12/12 19:23:23 ports: port 13 is now off-line
W 10/12/12 19:23:34 ports: port 13 PD Invalid Signature indication.
I 10/12/12 19:23:35 ports: port 13 is Blocked by STP
I 10/12/12 19:23:37 ports: port 13 is now on-line

But results are different because switch didin't learn mac addresses.

Is there any bug software that can lead to this effect or it could be cables? For me it doesn't have sense, one day switch learn mac address and another it doesn't.

Best Regards.

[16again]

Make sure speed and duplex settings on both sides of the link have matching settings. Reported collisions might indicate an issue.

Most other port messages are quite normal.