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When Rapid PVST+ is used, switch ports always enter the blocking state immediately after the boot process
1. The blocking state is the first of the five possible port states in the Rapid PVST+ protocol. In this state, the port does not forward frames but listens to BPDUs to determine the location of the root bridge and the best path to reach it 12. After a port enters the blocking state, it transitions to the listening state and then to the learning state before finally entering the forwarding state. When Rapid PVST+ (Per-VLAN Spanning Tree Plus) is used, switch ports go through a specific state immediately after the boot process. This state is known as the "discarding" state.