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CM3.2 etherchannel discovery

Hi,

recently we recognized that Campus Manger 3.2 is displaying all our Etherchannels in the Topology Services like "Ethernets" and not like direct connections. This makes the layout pretty annoying. Any idea about how to change the layout in the Topology services to a direct line between the two devices connected by a channel ?

1 REPLY
Blue

Re: CM3.2 etherchannel discovery

One possibility could be that when ANI discovers a link, the discovery first reads the interface information on the local port of

the device. The ANI discovery then contacts the CDP neighbor of that interface and reads the interface information of the remote port on the neighboring device. ANI also performs the same

procedure on the neighboring device. The result should be the same. In case there are multiple CDP neighbors on the interface (that is, the interface is attached to a hub and there are multiple Cisco devices attached to that hub), ANI repeats the process for every CDP neighbor.

Instead of showing a single link on the map, Campus represents the hub as a segment. If a link is missing, this means that the devices that are connected to the link cannot see each other through

CDP. Something could be blocking the CDP packets or one of the devices might not be advertising itself to its neighbors.

If Campus is wrongly showing links that directly connect two devices as segments, check if the information on both ends of the link is the same. Here's an example of two show cdp neighbors command outputs that don't add up:

Switch1# show cdp neighbor

Port Device-ID Port-ID Platform

-------- ------------- ------------------ -------------------

3/1 Router1 GigabitEthernet3 ciscoCat4232L3

3/2 Router1 GigabitEthernet4 ciscoCat4232L3

3/2 Router1 Port-channel1.1 ciscoCat4232L3

Router1# show cdp neighbor

Device ID Local Intrfce Holdtme Capability Platform Port

ID

Switch1 Port-channel1.1 163 T S WS-C4006 3/2

Switch1 Port-channel1.1 163 T S WS-C4006 3/1

The problem here is that the switch sees the router on three interfaces (remote interfaces GE3, GE4, and PC1.1) while the router sees the switch on two interfaces (remote ports 3/1 and 3/2). The result is that Campus shows the switch and router on a segment instead of three separate links. This behavior can also occur on Etherchannels. To resolve these discrepancies, make sure all the ports in the channel have CDP enabled.

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