20
Configuring System Information
EdgeSwitch
™
Administration Guide
Ubiquiti Networks, Inc.
Viewing ARP Cache
The ARP cache is a table maintained locally in each station on a network. ARP cache entries are learned by
examining the source information in the ARP packet payload fields, regardless of whether it is an ARP request
or response. Thus, when an ARP request is broadcast to all stations on a LAN segment or virtual LAN (VLAN),
every recipient has the opportunity to store the sender’s IP and MAC address in their respective ARP cache.
The ARP response, being unicast, is normally seen only by the requestor, who stores the sender information
in its ARP cache. Newer information always replaces existing content in the ARP cache.
The ARP cache can support 1,024 entries, although this size is user-configurable to any value less than 1,024.
When multiple network interfaces are supported by a device, as is typical of a router, either a single ARP
cache is used for all interfaces, or a separate cache is maintained per interface. While the latter approach is
useful when network addressing is not unique per interface, this is not the case for Ethernet MAC address
assignment so a single ARP cache is employed.
To display the system ARP cache, click
System
>
Status
>
ARP Cache
page in the navigation menu.
ARP Cache
ARP Cache Fields
Field
Description
MAC Address
Displays the physical (MAC) address of the system in the ARP cache.
IP Address
Displays the IP address associated with the system’s MAC address.
Interface
Displays the unit, slot, and port number being used for the connection. For non-stacking systems, only
the slot and port number is displayed.
For units that have a service port, the service port will be listed as
Management
in this field.
Use the buttons to perform the following tasks:
• Click
Refresh
to reload the page and refresh the ARP cache view.
• Click
Clear Entries
to clear all entries from the table. The table will be repopulated as new addresses are
learned.
