[Qemu-discuss] Why does this work on kvm but not soft emulation?

[Aryeh Friedman]

First 3 steps are on Intel running Ubunutu 12.04.3 LTS the rest are on AMD running FreeBSD 10-RELEASE

1. I create 10G drive (raw file format)

2. I install ubuntu onto it with:

#!/bin/bash
#

# Handwritten script

# Net set up
bridge=br0
tap=$(sudo tunctl -u $(whoami) -b)
ip link set $tap up
sleep 1s
brctl addif $bridge $tap

# call hyper v
kvm -drive format=raw,if=virtio,file=ubu -net nic,vlan=0,model=virtio -net tap,vlan=0,ifname=$tap,script=no -m 4096 -smb 3 -vnc :0 -disp
lay none -cdrom ubu.iso

# net break down
brctl delif $bridge $tap
ip link set $tap down
tunctl -d $tap

3. Shut down the VM from within the guest OS and kill the process

4. Copy the disk image over to the FreeBSD machine and start it with:

#!/bin/sh
#

# Generated by PetiteCloud

ifconfig tap37 destroy
ifconfig tap37 create
ifconfig tap37 up
sleep 5
ifconfig bridge0 addm tap37 up

qemu-system-x86_64 -drive format=raw,if=virtio,file=ubu -net nic,model=virtio -net tap,ifname=tap37 -smb 1 -m 2048 -vnc :0 -display none
echo $!>/var/run/petitecloud/rc5adn3358

5. The guest OS gets as far as disk checks and then dies (this does not happen under kvm)

--

Aryeh M. Friedman, Lead Developer, http://www.PetiteCloud.org