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Layer 3 Routing between Gigaman/MAN

We have a Gigaman/MAN connection between two offices that is currently setup with (2) Layer 2 switches as endpoints. We are looking to change this to Layer 3 routing between sites. We will be using a Catalyst 3750 (IP Services IOS) and a Cat 4006 (IP Services) as the endpoints. Is the configuration (EIGRP)on the switches any different than using 2 routers connected by a T1 (besides the serial interfaces)? Any other recommendations when configuring L3 across a MAN?


Re: Layer 3 Routing between Gigaman/MAN


the configuration with respect to IP routing is pretty much the same. You might want to investigate using summarization or EIGRP stub to limit the query range. Other than that it is straight forward.

The other thing which is usually causing much more hedache is IP readressing. Once the VLANs do not span your whole network you might have to readdress some portions of your network. In case this is also involving servers you might find some problems identifying all occurences of server IPs (like in scripts, client configs etc.).

Also make sure that all your applications are using IP unicast and are routable before moving to a routed backbone. I have seen apps which relied on broadcast, assuming every device is in the same subnet.

Hope this helps! Please rate all posts.

Regards, Martin


Re: Layer 3 Routing between Gigaman/MAN

It really depends how stretched was the VLAN. Also i'd suggest using /30 addresses for the point-to-point link.