Refer to the exhibit. An EtherChannel was configured between switches S1 and S2, but the interfaces do not form an EtherChannel. What is the problem?

Refer to the exhibit. An EtherChannel was configured between switches S1 and S2, but the interfaces do not form an EtherChannel. What is the problem?

• The interface port-channel number has to be different on each switch.
• The switch ports were not configured with speed and duplex mode.
• The switch ports have to be configured as access ports with each port having a VLAN assigned.​
• The EtherChannel was not configured with the same allowed range of VLANs on each interface.

Explanation: The guidelines for configuring an EtherChannel link are:
Interfaces which form an EtherChannel can be physically discontiguous, and on different modules.
Interfaces in an EtherChannel have to operate at the same speed and in the same duplex mode.
Interfaces in the EtherChannel must be assigned to the same VLAN, or be configured as a trunk.
Interfaces in the EtherChannel have to support the same allowed range of VLANs.

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