configuring EIGRP across network : several locations

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Aug 18th, 2009
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We are configuring EIGRP in our network. We have several locations across town using comcast to connect these sites back to the head office. Do we require to get an ASN Number from ARIN or can we use any number?

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yagnesh_tel Tue, 08/18/2009 - 09:55
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EIGRP ASN number is only relavant in your network. You dont need to ask them from ARIN as the case with BGP. So you can use any number from 1-65535.

Assuming that you are not planning to run EIGRP with carrier, you can build GRE tunnels between your location and run EIGRP on them.

Richard Burts Tue, 08/18/2009 - 09:57
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It is difficult to give you really good advice without knowing a bit more about how you plan to set up the connections and about what kind of service you will be getting from Comcast.

You would only use an ASN Number from ARIN if you were going to run BGP on these connections, and it is not likely that you would run BGP over a Comcast customer connection.

What most customers do in the kind of situation you describe is to set up IPSec VPN tunnels from the remote sites to the head office. There are a couple of options that would allow you to run your EIGRP through the tunnels between the sites (IPSec with GRE tunnels, and Virtual Tunnel Interface are the most likely options that come to mind).



JMC Nel Tue, 08/18/2009 - 10:06
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use a 3560's as L2 closet switches that is trunked to a 4507 edge (dist) switch which is set up as dhcp server and has vrf, svi and eigrp config.. the edge (dist) switch has a trunk to a 6509 core switch which has the same vrf, svi and eigrp config as dist switch. we have 3 interfaces at each location pointing to comcast which will encapsulate our traffic and deliver at destination 3 ports

jim_berlow Tue, 08/18/2009 - 10:36
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I see no reason why you would need a registered ASN from ARIN. Comcast should be able to give you the definitive answer, though.

Good Luck!


JMC Nel Tue, 08/18/2009 - 10:38
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thank you to all the enigneers that responded. I appreciate it.


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