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

[Martin_Hancock]

Hello

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.

[AEK]

Hi Martin

Did you check if there is DHCP snooping on the switch?

[Martin_Hancock]

DHCP snooping is turned off at the VLAN level.  How do i check it at the switch level?  The switches are connected via fortilink

[AEK]

At VLAN level you find it under "config switch vlan".

At port level you find it under "conf switch interface".

[Martin_Hancock]

I’ve checked that and I can’t find anything referring to DHCP snooping

[AEK]

Hi Martin

What is FortiSwitch firmware version?

[Martin_Hancock]

HI @AEK 

7.4.2 on my switching

[AEK]

Sorry you've already mentioned it before.

So, I think you said you are doing DHCP relay through FSW over VLAN (I understand trunk port), right?

If so, and if you like troubleshooting, I'd suggest to test the same but over an access port.

[Martin_Hancock]

I am testing with an access port.  My switches are connected via Fortilink

[jsauer]

I'm having a similar issue with DHCP relay and 7.4.3 (was .2, upgraded and issue still there). I'll be downgrading to 7.2.7 tonight to test and can report back my results tomorrow when I'm in the office again.

[Martin_Hancock]

Hi @jsauer 

Do you have forti switches as well?