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How do I configure 6509's for a 100 mbps NMLI connection????

I have searched various websites, including Cisco’s, for help in configuring Cisco 6509’s for a 100 mbps ethernet NMLI connection but haven’t been able to find anything helpful. Here is my scenario: we currently have a Bellsouth T1 connecting my building with our manufacturing facility. This T1 terminates in two IBM 2210 routers running OSPF. We will be installing a Bellsouth 100 mbps ethernet NMLI connection between these two buildings and will terminate them in a Cisco 4006 switch. The 4006 is connected to two Cisco 6509’s. We plan on keeping the existing T1 connection as a backup in case the NMLI goes down. I need to know how to configure the 6509’s for this new NMLI connection and most important how to make sure that the traffic traverses the NMLI link as it’s primary route. Does anyone have any ideas?


Re: How do I configure 6509's for a 100 mbps NMLI connection????

I havent dealt with a NMLI till now, but reading more on NMLI, i understand that its a shared fiber optic connection from Bell South.

Native Mode LAN Interconnection Service - NMLI. Mostly the NMLI connection should terminate on a box at either ends of your premises. These can be terminated either using copper or fiber to your switch. I think you ll be needing an ST type connector on your switch to connect to the box that Bell South installs on your premise.

New Member

Re: How do I configure 6509's for a 100 mbps NMLI connection????

The NMLI circuit is a great offering from BellSouth. Almost plug and play. Your NMLI circuit is actually two circuits. Each one of your two sites connect to one of BellSouth's switches. Kind of makes them a middle man. BellSouth brings the circuit in to each of your premises via a single mode fiber cable. The customer side of NMLI box demarc is multi-mode fiber. You can get a media converter should you want to connect this to your switch using a patch cable.

You will need a media converter at each site.

In the simplest of configurations you configure a port as a trunk on the switch at each location. Take the patch cable from your media converter and plug it in.

This is not unlike creating a 100 mb trunk between two switches that are sitting side by side in the same room. BellSouth is simply the middle man. With this in mind, make sure your switch configurations are such that you would want to trunk them together. Check your VTP settings carefully.

My redundant link caused a severe spanning tree problem on the BellSouth switch, so if possible, I would suggest disabling your T1 link until the NMLI link is up and forwarding traffic out of the NMLI trunk port on your switch.

New Member

Re: How do I configure 6509's for a 100 mbps NMLI connection????

Thanks very much. This is the most information I've seen on the configs for the NMLI connection.