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Problem with Metro Ethernet Service

We have been working with a local telco to get a metro ethernet connection up. We have over twenty sites on ME with a different telco with no problems. On our side we are using a Cat 3750 EMI that connects 100mb copper (access port non-trunk) to an Aktino device that connects to another Aktino at the CO using four pairs of copper wires, at the CO the Aktino connects 100mb copper to a Nortel 8610 router then this 8610 has a 1g connection to our other ME providor. For trouble shooting purposes I placed a hub on our side between the 3750 and the Aktino I then placed my laptop on the hub to capture traffic. I am able to see traffic from my other sites to the 3750 and I see ARP request coming from the 3750 and the arp replies from devices at other sites but doing a debug arp the switch is not seeing these replies, the laptop being on the hub also can ping the 3750 and the 3750 can ping the laptop so I know the port is good. I moved my laptop to the 3750 and set up a span port and the switch is not seeing any traffic inbound from the other sites. There has to be something that the Nortel 8610 is doing to the packets to make the 3750 ignore them or not see them. Any help would be appreiciated the local telco providor is clueless.

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Re: Problem with Metro Ethernet Service


The obvious possibility is that the 8610 is doing something like tagging the frames. If your 3750 access port receives a tagged frame I believe it considers it invalid and discards it. This would be consistent with the symptoms that you describe. Your PC capturing frames can process both tagged and untagged frames. Can you look at the traffic on the hub and look for evidence that the frames are tagged?



New Member

Re: Problem with Metro Ethernet Service

Thanks for your response, I know from experience that the internal nic on my laptop cant see the vlan tagging which is maybe why in the packets I captured I dont see it. I will go out there monday and check using another nic.

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