The original OP is remved because modified later for add spam.
Orphan post.
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What is the final purpose?
What would be the possible utility for others?
/ip arp print as-value where [:if ($status != "reachable") do={:ping $address vrf=main interface="bridgeLocal" arp-ping=yes count=1}]
/ip arp remove [find where status!="reachable" and interface="bridgeLocal"]