Arp Learning Via Arp Request - Dell C9000 Series Networking Configuration Manual

ARP Learning via ARP Request

The system learns via ARP requests only if the target IP specified in the packet matches the IP address of the
receiving router interface. This is the case when a host is attempting to resolve the gateway address.
If the target IP does not match the incoming interface, the packet is dropped. If there is an existing entry for
the requesting host, it is updated.
Figure 52. ARP Learning via ARP Request
When you enable ARP learning via gratuitous ARP, the system installs a new ARP entry, or updates an existing
entry for all received ARP requests.
Figure 53. ARP Learning via ARP Request with ARP Learning via Gratuitous ARP Enabled
Whether you enable or disable ARP learning via gratuitous ARP, the system does not look up the target IP. It
only updates the ARP entry for the Layer 3 interface with the source IP of the request.
IPv4 Routing 558