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New Contributor II

Issues with DHCP Relay following upgrade to 7.4.3 on 40F and 7.4.2 on Fortiswitch 124F


I have recently upgraded my Fortigate 40F unit to 7.4.3 and associated Fortiswitch 124F connected with Fortilink to version 7.4.2


Ever since i have done this my DHCP relay no longer works.  DHCP from the Fortigate interfaces work fine but when i enable DHCP relay there is no DHCP response and i cannot see any DHCP traffic being forwarded to my DHCP server.  I can ping my server with no issue.


Any assistance would be helpful.


No, Ubiquiti switches and access points. The VLANs all worked before I put the Fortigate in (was running a Sophos UTM) and with DHCP relay enabled on that device.

New Contributor II

Hi there


i have an update


after speaking to my WAN provider it turns out there was an issue at their end to do with Circuit ID Insertion selected as “PPoE Relay".  Once they changed this to something else the DHCP traffic could communicate with no issue.


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