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I'm trying to figure out how to create KVM VM. I'm doing this via virt-manager GUI on Ubuntu 12.10 host. What I did was that I downloaded the image we are using in Rackspace cloud ( ie. the tar.gz file) to the KVM host, then I tried to build the VM locally however as soon as the terminal window starts it looks like the image can't boot saying "no boot disk found". Strange thing is that it is first trying to PXE boot and then fails. Any ideas would be hugely appreciated.

Same thing happens if I try to use any of Ubuntu images. ie any of these

However when I follow the guide on this link: All works fine - obviously not something I'm looking for as I'd like to find out how to boot Rackspace cloud images.

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I've written a guide on how to run a rackspace image locally under Xen, but the steps for extracting the the disk image are the same.

Check steps 5-11 at, that should help you get a correct image for your KVM setup.

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Cloud images are not disk images, they are partition images and KVM needs a disk image. Disk image represents a whole disk, it has a partition table and can contain multiple partitions. I was able to mount an image from using mount -o loop ./precise-server-cloudimg-i386.img /mnt/ so this file was obviously a partition image. To mount these images in KVM you will need a working KVM VM created from scratch. You will have to create a second empty disk image and a fresh partition on it with a newly created filesystem. Then you will be able to attach your existing image and mount it as a whole, say mount /dev/sdc /mnt/existing-image. You will be able to rsync everything from your existing mounted partition image to your new disk image then. You will also need to setup GRUB to the MBR of your new disk image.

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Qemu, the core of KVM, can "boot" a separate kernel image file. The could either be the system kernel, or a PVGRUB image that loads the kernel in the whole disk filesystem per the GRUB config file there. I may try to boot that cloud image from uec-images on KVM/Qemu myself this weekend. – Skaperen Aug 21 '12 at 20:37
I got the UBuntu cloud images working by converting them into qcow2 and changing some options in virt-manager. Then I set the booting to floppy and all worked fine. The images are now booting without any problem. However, I havent got my head aroung that VHD issue. I tried to convert it to qcow2 - basically applying the steps which worked for Ubuntu images but it didnt work for this and the boot is - this time - handing indefinitely withe "Booting from the hard disk........." – gyre Aug 22 '12 at 9:07
Also @Alex, I'm not able to mount raw disk image created from the VHD one. Basically I converted VHD image to a raw image and then tried to mount a raw image as a loopback device but that doesn't work as I'm getting "no fs specified". I tried couple of Filesystems but none worked. – gyre Aug 22 '12 at 9:16

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