Symptoms:
PXE boot stuck at “Waiting for Approval”
If you virtualize a Distribution Point in SCCM and want to use it for PXE booting you need to make some changes in NSX-T in order to allow it to work.
PXE booting sends a DHCPREQUEST directly to your DPS. By default NSX-T blocks servers from getting or replying with DHCP requests.
To enable it for specific servers create a “Segment Security Policy” profile in NSX-T and disable DHCP Server Block
Create a new network segment with the correct VLAN and assign the policy you just created to it.
In VCenter move the DPs to the newly created segment.