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"Operating System Not Found" in VMware Console After Delphix Engine Upgrade or Reboot (KBA8347)




KBA# 8347



Following an upgrade or other reboot of Delphix Engine, the VM may fail to respond on network. Further investigation reviewing the Engine VM console may indicate "PXE-M0F: Exiting Intel PXE ROM" and "Operating System Not Found" messages.  Repeated attempts to reboot the VM does not alter the observed behavior. 



Delphix Engine deployed on any supported version of VMware.

Applicable Delphix Versions

Click here to view the versions of the Delphix engine to which this article applies
Major Release All Sub Releases





Resolution - Update BIOS Boot Order

In some VMware ESX configurations, an improper boot order may be configured in the VM BIOS, directing the VM to attempt boot from network before local storage.  This may be indicated by the accompanying VM console events indicating "Network boot...":


In order to confirm and correct this behavior, the VM Options (accessed via Actions > Edit Settings in vSphere) can be altered to enable "Force BIOS setup" on the next reboot. Then, reboot the VM to access the BIOS settings.

In this step, it should also be confirmed that Firmware is set to BIOS.

On the next boot, the VMware administrator can navigate to the Boot tab in the BIOS menu and review and correct the boot order as needed.

In the following example, Network boot from VMware VMXNET3 is above/before Hard Drive, meaning the VM will attempt to boot from the network first.


In the following screenshot example, the Hard Drive options are expanded to illustrate a typical Engine configuration; the number of devices in any configuration may vary. As illustrated, Network boot from VMware VMXNET3 is included after the Hard Drive devices, ensuring that the Engine root disk (0:0) is used first.


It is important to understand, Delphix (and really, any guest Virtual Machine) does not have the ability to modify this parameter from a running OS.  There is currently no known guest API or access to alter BIOS settings on a running VM, and in more recent VMware releases, the parameters related to BIOS (bios.bootOrder) are no longer an advanced setting associated with the VM, and are not present in the VM .vmx files.

An administrator interaction is the only known method for these values to be explicitly changed, and also requires disruption as the VM must be rebooted to the BIOS interface.  

In the instance that the VM hardware configuration is altered, it is possible that device reordering may result in implicit boot order changes on the next reboot.

If this issue is encountered and root-cause is desired, VMware Support must be engaged for further assistance.

Resolution - Update Boot Order By Editing .vmx File

If more than 8 disks are provisioned to the Delphix Engine VM, the Hard Drive selections presented in BIOS may not allow for the selection of Virtual SCSI Hard Drive 0:0. In that case, the configuration file for the Delphix Engine can be edited by a VMware administrator to explicitly set disk 0:0 as the boot device.

As this is a VMware administrative task, it is recommended to reference the VMware Knowledge Base document links provided in the section below, and work with an Administrator or your VMware support vendor to complete the task of manually editing the .vmx file, as this can render the Engine unbootable if mistakes occur.