Turbocharge Your IT Journey: Ace the Cisco Certified Network Pro Test 2025 – Network Ninja Style!

Setting the mode to 'Auto' in Port Aggregation Protocol (PAgP) means that the port will automatically negotiate with the other end of the connection to join the EtherChannel if the remote side is properly configured to support it. This mode allows the switch to respond to PAgP packets sent by the far side and become a member of an EtherChannel if both ports are compatible and configured correctly.

In this scenario, 'Auto' does not actively initiate the formation of the EtherChannel on its own; rather, it waits for a negotiation to occur, making it dependent on the configurations of the remote ports. If the far side is correctly set up to either 'Desirable' or 'Auto', the port configured in 'Auto' mode will successfully join the EtherChannel, thus providing an effective means of link aggregation.

The other options do not accurately reflect the operation of PAgP in 'Auto' mode. Non-operational ports do not pertain to this setting, 'active' doesn't apply since 'Auto' does not enforce a specific EtherChannel state, and sending PAgP packets only when needed does not capture the proactive negotiation nature of PAgP in general.