Strict ARP learning is enabled on S series switches, and the user has learned the switch's ARP entry. Why cannot the switch learn the user ARP entry by pinging the user

For S series switches:
After strict ARP learning is enabled, the switch learns ARP entries only from the Reply packet sent in response to locally originated ARP Request packets.
The firewall installed on the PC may prevent the PC from sending ARP Reply packets when receiving ARP Request packets, or the NIC on the computer cannot return ARP Reply packets. In this case, the switch cannot receive ARP Reply packets no matter whether the switch sends ping packets to the user or the user sends data packets to the switch to trigger ARP Miss messages. Therefore, the switch cannot learn the user's ARP entry.
If this problem occurs on only a few users, configure static ARP entries for the users; if the problem happens on most users, disable strict ARP learning on the switch.

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