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vusal_d
New Contributor

One mac address many local iodresses - device detection

Can someone explain why this mac address appears every 5 seconds. It is source ip always different. It stopped appearing after I disabled “Device Detection” on LAN interface.

1 Solution
lobstercreed
Valued Contributor

Hi Vusal,

 

Same MAC address on same LAN port (port10) every time, right?  This is the MAC address of whatever router sits inside your firewall.  Since all traffic routes through it, it's the only device the FortiGate has Layer 2 visibility to see.  So whether it's forwarding a packet from 1.2.3.4 or 5.6.7.8 it will always present the same MAC address on the interface facing the firewall.  This is elementary OSI model stuff.  :)

 

- Daniel

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3 REPLIES 3
lobstercreed
Valued Contributor

Hi Vusal,

 

Same MAC address on same LAN port (port10) every time, right?  This is the MAC address of whatever router sits inside your firewall.  Since all traffic routes through it, it's the only device the FortiGate has Layer 2 visibility to see.  So whether it's forwarding a packet from 1.2.3.4 or 5.6.7.8 it will always present the same MAC address on the interface facing the firewall.  This is elementary OSI model stuff.  :)

 

- Daniel

vusal_d

lobstercreed wrote:

Hi Vusal,

 

Same MAC address on same LAN port (port10) every time, right?  This is the MAC address of whatever router sits inside your firewall.  Since all traffic routes through it, it's the only device the FortiGate has Layer 2 visibility to see.  So whether it's forwarding a packet from 1.2.3.4 or 5.6.7.8 it will always present the same MAC address on the interface facing the firewall.  This is elementary OSI model stuff.  :)

 

- Daniel

Thank you for explanation Daniel. Very helpful

jubaa006
New Contributor

So how i can fix it to see all mac address for all source ips ?

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