<h2>ARP property documentation for Service Mapping</h2><br/><div style="overflow-x:auto"><article><div ><h3 >Summary</h3><section><div><strong>Background:</strong></div> <div>As part of an analysis that Platform team did, it was noted that querying 'discovery_net_arp_table' around is quite expensive.</div> <div>Therefore the queries on this table need to be limited</div> <div> </div> <div><strong>Uses:</strong></div> <div>In Service Mapping,</div> <div>Use of 'discovery_net_arp_table' is limited to detect switches and router on Layer 3 network path. There is no other feature which uses this table.</div> <div> </div> <div>The method to find the outgoing port IDs to add routers for calculating the layer 3 path uses three strategies:</div> <div>First strategy: look for port whose IP matches the next host IP</div> <div>Second strategy: look for the outgoing port in the routing table</div> <div>Third strategy: look in the ARP table of adjacent devices</div> <div> </div> <div><strong>Property:</strong> sa.network_path_calculation.arp_enable</div> <div><strong>OOB Value:</strong> false</div> <div> </div> <div><strong>Property value 'false':</strong> The network path for layer 3 network hops, which doesn't get the outgoing port IDs using the first and second strategies as mentioned above, cannot be calculated. Thus, the network path map, will not contain the layer 3 network hops.</div> <div> </div> <div><strong>Property value 'true':</strong> The network path for layer 3 network hops, which doesn't get the outgoing port IDs using the first and second strategies as mentioned above, can be calculated of the corresponding record is present in the ARP table. Thus, the network path map, will contain the layer 3 network hops.</div></section></div></article></div>