Flex System x240 M5 PXE not booting

Hello, today I stumbled upon another problem. x240 M5 compute node did't start from PXE.
On pxe server I had tftp error:

tftp: client does not accept options

Problem wasn't on PXE server side, it was compute node configuration issue, more precisely - NIC config. So to resolve it one has to do following:

1. Log in to server's IMM (you can't do it from chassis CMM, it needs to be done from IMM) and go to Server Management --> Adapters.

2.   Next, select you ethernet adapter. In my case it is Flex System EN4172 2 port 10 Gbit Ethernet Adapter

3. Go to configuration tab and under "MBA Configuration Menu" change "Legacy Boot protocol" from NONE to PXE.

4. Reboot the node, it should now boot from PXE if you have legacy mode enabled*.


(maybe it'll work with UEFI also, but didn't veriy it)

Update: I checked and it doesn't work with UEFI...