Glossary

ARP Learning via ARP Request
In Dell EMC Networking OS versions prior to 8.3.1.0, Dell EMC Networking OS 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 53. ARP Learning via ARP Request
Beginning with Dell EMC Networking OS version 8.3.1.0, 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 54. 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.
Configuring ARP Retries
You can configure the number of ARP retries.
The default backoff interval remains at 20 seconds. On the device, the time between ARP resend is configurable. This timer is
an exponential backoff timer. Over the specified period, the time between ARP requests increases. This time increase reduces
the potential for the system to slow down while waiting for a multitude of ARP responses.
To set and display ARP retries, use the following commands.
● Set the number of ARP retries.
CONFIGURATION mode
arp retries number
432
IPv4 Routing