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How to block internet access by Mac address!

Hi all,

I am using fortigate 300C V5.0 .

I want to block internet some Pcs by Mac address,so when i created an policy device identity with Authentication Rules action=Deny,All pcs couldn't access internet.

Kindly help to fix this issues!

Many thanks


New Contributor

With v5.2 we've done this a few ways... Only one is leveraging MAC addresses though...


Option 1 - (if machine is permanently blocked from internet)

  > Open DHCP monitor > right-click DHCP lease > create/edit IP Reservation > set action "Block"


Option 2 - (if you want all users to authenticate - I use this option since we have many users using the same computer so I can't block a certain machines MAC.  Put policies above this policy for internal traffic "ie: intranet sites, services, etc..")

  > Create policy: Internal > Src=DHCP scope/all computers > User Group or User > Internet > All > ALWAYS > All


I believe on v5.0 you can find the same settings stated in Option 1 under "System>Network>Interfaces" and look for your internal network handing out DHCP leases (if done locally with Fortigate).  Click the "Advanced.." hyperlink and add MAC addresses with appropriate action. Hope some of this helps.


Enable "Device Management --> Detect and Identify Devices" on your LAN interface


Under User&Device --> Device --> Device definitions create a group of blocked MAC IDs


In your firewall policy block the device group you need blocked (scales) but allow ALL





Thanks for your help!

I already configured fortigate follow your advice but still deny all user access internet.


According to your screenshot above you DENY for both scales and ALL


I understood!but the second line in the Authentication Rules is default of Fortigate,i could not Edit this rule.

Could you advice me!


Try to add an "ALL-ALL-ACCEPT" rule, and see what happens.

Ede Kernel panic: Aiee, killing interrupt handler!
Ede Kernel panic: Aiee, killing interrupt handler!

I need to prevent internet access by mac filtering but not wireless internet connection. I need to block wired internet connection. How I have to perform the rule? I have fortiguard 90d..

You have hijacked a thread that is already over one year old. Please start a thread on your own.

Second, supply sufficient information so that one can help - version of FortiOS, at least.

Ede Kernel panic: Aiee, killing interrupt handler!
Ede Kernel panic: Aiee, killing interrupt handler!

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