Packer Created VMs Failing to Boot

mtcoffee

After posting this I ended up building out a sample project and shared on github.
https://github.com/mtcoffee/xcp-ng-packer-examples

fatek

@mtcoffee talk about great timing?
About 25 minutes ago, I git cloned your repo!
Thanks.

fatek

@mtcoffee Any luck getting autounattend.xml - UEFI to work?

mtcoffee

@fatek

I noted that in the packer file. I was not able to get packers floppy_files working in uefi mode.

@ddelnano might have some insight?

fatek

Anyone know where the @ddelnano Discord channel is?

olivierlambert

https://discord.gg/Cp2CDhqd

fatek

@olivierlambert thank you

fatek

I would really love to get this working w XCP, no bios, I mean uefi only.
Packer was super easy to setup on ESXi + vCenter!

olivierlambert

Contributions are welcome, we are pretty busy here, and if we planned to have a fully dedicated "Devops" team, it will be in place in September. So please be patient, we do not have 5000 engineers

mtcoffee

@olivierlambert is spot on. Manage expectations. The best thing we can do is contribute helpful information.

Here is what I was able to deduce when this issue came up.

When creating a Windows VM in uefi mode and using the floppy_file option in packer:

There is a disk added as "fda"
However the fda device is not available as the a: drive or any other drive letter. When booted using bios mode, you can find the fda device by settting drive letter to "a:".

This is likely because uefi typically does not support floppy disks. I believe in VMWare when the floppy_file option was used in UEFI mode, it added the ISO as a DVD drive instead of an FDA.

Not sure if this is best solved at the Packer level or if it should be intercepted and corrected XCP-ng level?

fatek

I hear you regarding "managing expectations".

If Vates (as a company) is going to claim they offer VMware type/like value then Windows can not be a 2nd class citizen in your ecosystem!

fatek

@mtcoffee It seems like getting Packer involved would be the way to go but I have zero idea on what is involved.

Looking at vSphere ISO docs, there is the option to create cdrom configs and also another option to use cd_files (list of files to place on to a CD that is attached when the VM is booted).

I don't see that option in the XenServer-iso docs.

olivierlambert

@fatek To be clear, absolutely nobody on the market has an equivalent to VMware. Nobody. We never told we could replace entirely all the VMware product.

Obviously, we'd like to close the gap as fast as possible, but the fact Vates is entirely privately bootstrapped and privately owned means we cannot burn VC's money at the pace of Nutanix for example.

fatek

@fatek said in Packer Created VMs Failing to Boot:

they offer VMware type/like value

@olivierlambert Yes, I am aware & not suggesting you spend money like a drunk sailor!
That is why I said "vmware like value"

fatek

@mtcoffee said in Packer Created VMs Failing to Boot:

Not sure if this is best solved at the Packer level or if it should be intercepted and corrected XCP-ng level?

@olivierlambert Just curious if this is more of a Packer issue or does the solution have to come from the Vates side?

olivierlambert

I don't know because I didn't have time to take a deeper look

fatek

Any updates on this uefi issue?

olivierlambert

Maybe @AtaxyaNetwork has a clue, otherwise it will have to wait for William arrival in the next weeks

@ddelnano is probably ultra busy now

mikand

Edit: Just had a thought, no idea if it's another potential workaround. In the builder you specify a template to clone that is used to create the VM. I'm on Xenserver 8, and there is no way through the GUI, but I think it might be possible to add an extra DVD-drive to a template? If that gets brought over to the packer vm, then that might be an option. Might need to do an eject from within the vm in order to dismount the dvd in order to not have it be part of the artifact though.

@olivierlambert Sounds like the best way forward would be to add the equivalent of the Hyper-V builder's secondary_iso that mounts a second iso-file, or even better cd_files which creates a temporary iso for you and mounts it.

For anyone who wants to test building eufi machines until this is solved, I have a Powershell script that takes a Windows ISO and generates a new one with files added (in my case autounattend.xml, bootstrap.ps1 and the management agent msi. Though I should change it to just download the msi instead to avoid rebuilding it.)

Since I was building a new ISO anyway, I also changed the boot loader to the noprompt one in order to avoid the timing issues with boot_commands and "Press any key to boot from DVD...."

The script uses oscdimg.exe that's included in the Windows ADK, which can be found here:
https://learn.microsoft.com/en-us/windows-hardware/get-started/adk-install

# Settings
$Architecture    = "amd64" # Or x86
$InputISOfile    = "D:\Deploy\ISO\Windows Server 2022 Eval.iso"
$OutputISOfile   = "D:\Deploy\ISO\Windows Server 2022 Eval XenServer.iso"
$TempFolder      = "E:\Temp\Win2022XenServer"
$AdditionalFiles = @(
	"C:\files\Autounattend.xml",
	"C:\files\bootstrap.ps1",
	"C:\\managementagentx64.msi"
)

$OSCDIMG_Path = "C:\Program Files (x86)\Windows Kits\10\Assessment and Deployment Kit\Deployment Tools" + "\$Architecture\Oscdimg"

# Check environment
If (!(Test-path $InputISOfile)){ Write-Warning "Input ISO file not found. Exiting";Break}
If (!(Test-path $OSCDIMG_Path)){ Write-Warning "OSCDIMG Path not found. Exiting";Break}
if((Test-Path $TempFolder)){ Write-Warning "Temp folder $TempFolder exists. Exiting.";Break}
foreach($file in $AdditionalFiles) {
	if(!(Test-Path $$file)){ Write-Warning "Additional file $file does not exists. Exiting.";Break}
}

# Mount the original Windows ISO and figure out the drive-letter
Mount-DiskImage -ImagePath $InputISOfile
$ISOImage = Get-DiskImage -ImagePath $InputISOfile | Get-Volume
$ISODrive = [string]$ISOImage.DriveLetter+":"

# Copy ISO contents to temp dir and add additional files
New-Item -Path $TempFolder -ItemType Directory -Force
Copy-Item "$ISODrive\*" $TempFolder -Recurse
if(($AdditionalFiles) -and $AdditionalFiles.Length -gt 0) {
	Copy-Item $AdditionalFiles $TempFolder
}

# Dismount the Original ISO
Dismount-DiskImage -ImagePath $InputISOfile

# Create a new bootable Windows ISO file, based on the Original ISO, but using efisys_noprompt.bin instead
$BootData='2#p0,e,b"{0}"#pEF,e,b"{1}"' -f "$TempFolder\boot\etfsboot.com","$TempFolder\efi\microsoft\boot\efisys_noprompt.bin"
  
$Proc = Start-Process -FilePath "$OSCDIMG_Path\oscdimg.exe" -ArgumentList @("-m","-o","-bootdata:$BootData",'-u2','-udfver102',"$TempFolder\","`"$OutputISOfile`"") -PassThru -Wait -NoNewWindow
if($Proc.ExitCode -ne 0)
{
    Throw "Failed to generate ISO with exitcode: $($Proc.ExitCode)"
}
Get-FileHash -Path $OutputISOfile -Algorithm SHA256
Remove-Item $TempFolder -recurse -force