I am not sure what is happening exactly. You can try couple of things to get some clue. Probably you can try to use some of the eigrp debugging commands like 'debug eigrp packet' or 'debug ip eigrp neighbor' command to see what is happening. You may be able to see some difference in the debugs when the new Ethernet is connected and disconnected. You can also try looking at the CAM table entries on the 2900 switch to see if there is any difference with and without the ethernet connection. Another thing that you can try is connecting a network analyzer tool and capturing the packets and analysing them.
The new remote must have a router on the same ip net as your routers are using on the switch with an address that you gave them. You must have also given them an address to be their next hop to reach the internet. It sounds like they got it backwards and are using the next hop as their routers address. When you plug them in they are taking over the address of one of your routers.
Check the arp tables of all of the routers addresses on the switched lan before you plug them in. Plug them in ,ping around and check the arp tables again. See if the mac addresses in the tables change. Use the mac-address table to figure out where the addresses in the arp table plug into the switch.
We are pleased to announce availability of Beta software for 16.6.3.
16.6.3 will be the second rebuild on the 16.6 release train targeted
towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are
looking for early feedback from customers befor...
Introduction Featured Speakers Luis Espejel is the Telecommunications
Manager of IENova, an Oil & Gas company. Currently he works with Cisco
IOS® and Cisco IOS XE platforms, and NX to some extent. He has also
worked as a Senior Engineer with the Routing P...
In this session you can learn more about Layer 3 multicast and the best
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