關於KVM，guest OS 無法安裝問題 - Linux

root# kvm-img create testubn.img 10G -f qcow2
創建IMG檔沒問題
root# qemu-system-x86_64 -smp 2 -m 1024 -net nic -net
tap,ifname=tap0,script=no,downscript=no -hda /vm/testubn.img -cdrom
/vm/ubuntu-12.04.2-server-amd64.iso -boot d -vnc :1
開啟VM也沒問題

可是我從VNC連進去後

Booting from DVD/CD...
Boot failed : Could not read from CDROM (code 0004)
Booting from Floppy...
Boot failed : Could not read the boot disk

Booting from Hard Disk...
Boot failed : not a bootable disk

Booting from ROM...
iPXE (PCI 00:03.0) starting execution...ok
iPXE initialising device...ok

...
...
...(這幾行是它想嘗試用網路開機....)

No bootable device

我是第一次灌虛擬機...不知道自己錯在哪裡.....
希望有大大能開導....
順帶一提..我使用的是ubuntu-server 13.04 64bit位元
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