UEFI Boot - Kernel panic: Unable to mount root fs on /dev/ram0

[mbghost]

I’m facing an issue when PXE booting on PCs with UEFI. The boot fails with the following error:

Kernel panic - not syncing: VFS: Unable to mount root fs on "/dev/ram0" or unknown-block(1,0)
Kernel Offset: disabled
---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on "/dev/ram0" or unknown-block(1,0)
This issue only happens on UEFI clients — legacy BIOS boots work fine.

What I’ve tried:
Tested different DHCP boot file options: ipxe.efi and snponly.efi — same result
Tried both latest and older versions of bzImage and init.xz — no change

The DHCP server runs on the same FOG Project server.
My topology is: ESXi Host → Cisco Switch → Client.
Other PCs with BIOS boot normally - but UEFI clients always fail with the error above.

Any ideas what might be causing this or how to fix it?

Thanks in advance!

[george1421]

@mbghost This error message baffles me. If its happening where I think its happening its not a pxe boot issue. This error happens after you pick an iPXE menu item or if you tell a computer to image.

So you can probably rule out ipxe.efi/snp.efi here.

This error message is generated with FOS linux is booting. The kernel has booted and when it goes to connect to init.xz the format of init.xz is corrupt for some reason.

What version of FOG are you running
What version of “the kernel” are you running?
What version of init.xz are you running (get this from a bios computer that boots. the version of the init will be under the fog logo)

What computer is this happening on (make and model)?
Is it all uefi systems or only from one manufacture?
How much ram does this computer have?
Are you seeing both bzImage and init.xz get transferred completely to the target machine. This will be visible just after you pick an item on the FOG iPXE menu.

To me this error is telling me something is wrong with init.xz or for some reason bzImage is not the right kernel for init.xz