Gratuitous Arp Settings - D-Link DGS-3600 Series User Manual

Gratuitous ARP Settings

An ARP announcement (also known as Gratuitous ARP) is a packet (usually an ARP Request) containing a valid SHA and SPA
for the host which sent it, with TPA equal to SPA. Such a request is not intended to solicit a reply, but merely updates the ARP
caches of other hosts which receive the packet.
This is commonly done by many operating systems on startup, and helps to resolve problems which would otherwise occur if, for
example, a network card had recently been changed (changing the IP address to MAC address mapping) and other hosts still had
the old mapping in their ARP cache
To open the Gratuitous ARP Settings window, click L3 Features > Gratuitous ARP Settings, as shown below.
Once you have made the desired gratuitous ARP setting changes, click Apply.
To modify a current entry, click the corresponding Modify button of the entry, which will reveal the following window to be
configured:
The following fields can be set or viewed:
Parameter
Send on IPIF status
up
Send on
Duplicate_IP-
_Detected
Gratuitous ARP
Learning
Gratuitous ARP
®
xStack DGS-3600 Series Layer 3 Gigabit Ethernet Managed Switch
Figure 8- 19. Gratuitous ARP Settings window
Figure 8- 20. Gratuitous ARP Table – Edit window
Description
This is used to enable/disable the sending of gratuitous ARP request packets while an IPIF
interface comes up. This is used to automatically announce the interface's IP address to other
nodes. By default, the state is Disabled, and only one ARP packet will be broadcast.
This is used to enable/disable the sending of gratuitous ARP request packets while a duplicate
IP is detected. By default, the state is Disabled. Duplicate IP detected means that the system
received an ARP request packet that is sent by an IP address that matches the system's own
IP address.
This is used to enable/disable updating ARP cache based on the received gratuitous ARP
packet. If a switch receives a gratuitous ARP packet, it should add or update the ARP entry.
This is Disabled by default.
The switch can trap and log IP conflict events to inform the administrator. By default, trap is
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