Description

The following article describes an issue for Juniper Networks EX/QFX Series Switches, in which the Juniper switch is not re-broadcasting DHCP offer packets back and how to fix this issue.

Symptoms

PXE is not working because DHCP is not completed.

Solution

Make sure the DHCP server does not strip DHCP option 82 from offers. This option is required for Juniper DHCP forward-only to work correctly. This can be verified in the DHCP offers being sent back from the DHCP server.

You can verify this on a packet capture by using the Transaction ID from the Discover and then filter it out with the option "bootp.id == <value>" to better find it. 

Modification History

2023-05-02: KB created.
2023-12-19: Added how to filter it using pcaps.