iPXE as PXE servers discover tool

[pogarek]

The problem is that I don't have access to DHCP server. That is what I want to do : discover PXE/DHCP responses/offers for a port in switch to check if they are valid.
In the current environment there is a mess with PXE booting: wrong (probably) entries on iphelpers, incorrect 66-67 options etc.
I want to nail it down - find what gives me the reply, what is in the reply, then I'll find owner of DHCP/PXE offer, I'll correct/disable it and repeat the procedure.