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How is the ARP entry MAC address of the next-hop destination in the FIB get?

Assume that a host sends a packet to a destination IP address and that the CEF-based switch does not yet have a valid MAC address for the destination. How is the ARP entry (MAC address) of the next-hop destination in the FIB get?
Exhibit

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A.
The sending host must send an ARP request for it

B.
All packets to the destination are dropped

C.
The Layer 3 forwarding engine (CEF hardware) must send an ARP request for it

D.
CEF must wait until the Layer 3 engine sends an ARP request for it

Explanation:
If a valid MAC address for the destination is not found, the Layer 3 forwarding engine cant forward the packet in hardware due to the missing Layer 2 next-hop address. Therefore the packet is sent to the Layer 3 Engine so that it can generate an ARP request (this is called the CEF glean state)

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