[How To]: Resolve Two Filesystems With The Same UUID Have Been Detected
What’s The Problem?
ESXi would be installed on different type of storage hardware such as SAN storage, local disk, portable devices. So you can install ESXi on different storage device but on same server hardware.
Let’s review a scenario of using different storage device:
You have installed ESXi on local disks and now your server’s array controller has problem. Local drives are healthy but ESXi wont boot from local drives. At this situation, booting ESXi via USB devices is a solution to hardware troubleshooting.
You will boot the server into new ESXi via USB device and flash array controller then the problem is resolved.
If USB device is still connected to USB port after reboot and logical drives are not selected as first boot device, you’ll face with purple diagnostic screen like the below:
The system has found a problem on your machine and cannot continue.
Two filesystems with the same UUID has been detected. Make sure you do not have two ESXi installations.
It also might be happened if you have installed ESXi on SAN storage and you forget remove the installation and the volume is presented to the server yet.
What’s The Solution
VMware has explained the solution on this KB article: https://kb.vmware.com/s/article/1035107
To resolve this issue:
- Restart the system.
- During the reboot, when the hypervisor screen appears, press Shift+O.
- In the boot option, type
overrideDuplicateImageDetectionand press Enter.
After the system starts, use any one of these methods to remove the duplicate ESXi installation:
- Identify the drive on which you want to remove the ESXi installation, and run this command from the console:
# dd if=/dev/zero of=/dev/disks/mpx.vmhba1\:C0\:T0\:L0 bs=1m conv=notruncFor more information, see Identifying disks when working with VMware ESX (1014953).
- Initialize the disk from the BIOS of the SCSI controller, if available.
- Install other guest operating systems on the disk that contains the duplicate installation of ESXi.
- Use the vSphere Client to add the datastore to another ESXi/ESX host and format the disk (volume) that contains the duplicate installation.