D-Link DES-3028, User Manual

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DES-3028 DES-3028P DES-3028G DES-3052 DES-3052P Layer 2 Fast Ethernet Managed Switch
Gratuitous ARP Settings
This window will show the Gratuitous ARP Settings on the Switch. An ARP announcement (also known as Gratuitous ARP) is a
packet (usually an ARP Request) containing a valid SHA (Sender Hardware Address) and SPA (Sender Protocol Address) for the
host which sent it, with TPA (Target Protocol Address) equal to SPA. Such a request is not intended to solicit a reply, but merely
update the ARP caches of other hosts which receive the packet and determine if there are any IP conflicts.
To view this window click
Monitoring
>
Gratuitous ARP Settings
.
Figure 11- 26. Gratuitous ARP Settings window
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 to be modified, revealing the following window to
configure:
Figure 11- 27. Gratuitous ARP Table – Edit window
The following fields can be set or viewed:
Parameter Description
Send on IPIF status
up 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
Enabled
, and only one ARP packet will be broadcast.
Send on
Duplicate_IP-
_Detected
This is used to enable/disable the sending of gratuitous ARP request packets while a duplicate
IP is detected. By default, the state is
Enabled
. 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.
Gratuitous ARP
Learning
This is used to enable/disable updating ARP cache based on the received gratuitous ARP
packet. If a switch receives a gratuitous ARP packet and the sender’s IP address in its ARP
table, it should update the ARP entry. This is
Enabled
by default.
Gratuitous ARP
Trap & Log
The switch can trap and log IP conflict events to inform the administrator. By default, trap is
Disabled and event log is Enabled.
Gratuitous ARP
Periodical Send
This is used to configure the interval for the periodical sending of gratuitous ARP request
packets. By default, the interval is 0.
255