Description:
PXE server is available, other machines can boot from this PXE server successfully, but Dell E6330 can't boot from this PXE Rep.
The error message is: PXE-E51, No DHCP or Proxy DHCP offers were received.
Cause:
The issue could be related to the Spanning Tree Protocol common to Cisco, Dell and other managed switches. The newer Dell System BIOS has a limited time out when PXE booting to a system during the imaging process. One workaround would be to press the Pause on the keyboard (i.e. the key combination on a Latitude E6400,) as soon as the DHCP cursor starts spinning on the display. Wait approximately 30 seconds then press the up arrow to resume the DHCP process. Note that if the DHCP response is not received by the third “dot”, the system is no longer looking for DHCP even though more dots are showing.
Resolution:
Shutdown STP.