I recently installed 8 new Dell PowerEdge c6220 II servers with dual 10G ports with CentOS 6. Each server has a DHCP reservation configured from a Microsoft 2003 DHCP server.
I am using a Bootutil program by Intel that enables PXE booting with these NIC's as required based on a solution provided by Dell support 2 years ago. For some strange reason, 5 of the servers are getting a DIFFERENT IP address during the PXE boot process, but when the OS boots, the reserved IP address is correctly obtained.
I have searched the DHCP server for the IP that it obtained during PXE boot and noticed that in the "Assigned IPs" pane, under the unique identifier column there is a GUID number rather than a MAC address like it should be.
I deleted the entry and tried re-adding the reservation, but nothing works.
For example: a host with a reservation for 10.0.0.10, obtains another IP address during PXE boot. But after the OS boots, it obtains 10.0.0.10
I would appreciate it if someone could help me figure out the problem.
Best Answer
1) A Wireshark capture will help to see if the PXE DHCP requests use the expected MAC addresses or not.
2) The PXE DHCP request and the following DHCP request include different parameters. Please check that your reservation rule is not overlapped for some other rule taking precedence in the case of a PXE DHCP request.