How do I show the ARP table in FortiGate command line?

This article describes how to display the ARP table on a FortiGate unit, configured in NAT mode.

Scope: FortiOS firmware versions 4.0 MR3 or 5.0.x.
When VDOMs are not enabled:
When VDOMs are enabled:
FGT # config vdom. FGT (vdom) # edit root. current vf=root:0.
FGT (root) # get system arp.

What CLI command shows the ARP table?

arp -a
To display the ARP table on a Unix system, just type “arp -a” (this same command will show the arp table in the command prompt on a Windows box, by the way). The output from arp -a will list the network interface, target system and physical (MAC) address of each system.

What are the entries in the ARP table?

Static ARP entry

Long static ARP entry—It is directly used for forwarding packets. A long static ARP entry contains the IP address, MAC address, VLAN, and output interface.
Short static ARP entry—It contains only the IP address and MAC address.
Multiport ARP entry—It contains the IP address, MAC address, and VLAN.

How do I edit an ARP table?

Modifying an ARP Entry Click IP Configuration > ARP Table. The Edit ARP Entry Page opens. Select an interface and click Edit. The Edit ARP Entry Page opens.

How do you clear the ARP table in FortiGate?

Layer 2 and layer 3 TCP/IP diagnostics

The execute clear system arp table command to remove the ARP cache.
The diagnose ip arp delete command to remove a single ARP entry.
The diagnose ip arp flush command to remove all entries associated with a single interface.

How do you Traceroute in FortiGate?

Enter “tracert com” to trace the route from the PC to the Fortinet web site. Trace complete. The first, or the left column, is the hop count, which cannot go over 30 hops. When that number is reached, the traceroute ends.

What is the purpose of the ARP Cache?

An Address Resolution Protocol cache (ARP cache) is a repository for data that is used to connect an IP address to a Media Access Control (MAC) address for a physical machine or device in a local network.

How do ARP tables work?

ARP broadcasts a request packet to all the machines on the LAN and asks if any of the machines are using that particular IP address. When a machine recognizes the IP address as its own, it sends a reply so ARP can update the cache for future reference and proceed with the communication.

What is the difference between ARP table and MAC table?

It is composed of the IP address and its MAC ADDRESS. The ARP table is a result of an ARP request after the ARP reply is received. MAC table holds the information of where a device is connected in a switch of a LAN , It answers the question : In what port of a switch is connected device with MAC address?

Do routers have ARP tables?

The router has an ARP table for every interface, usually one for LAN and one for WAN for home routers.

Why do we need an ARP table?

ARP Table is used to keep the record of the IP address and MAC address of the devices (source and destination device). For the communication between two devices, it is necessary that the IP address and the MAC address of the source and the destination device should be stored in an ARP table.