@@ -229,15 +229,8 @@ EOF

 ROOTFS=$VM_DIR/root

 mkdir -p $ROOTFS

-# Make sure we have nbd-ness

-modprobe nbd max_part=63

-

-# Which NBD device to use?

-NBD=${NBD:-/dev/nbd$GUEST_NETWORK}

-

 # Clean up from previous runs

 umount $ROOTFS || echo 'ok'

-qemu-nbd -d $NBD || echo 'ok'

 # Clean up old runs

 cd $VM_DIR

@@ -246,12 +239,27 @@ rm -f $VM_DIR/disk

 # Create our instance fs

 qemu-img create -f qcow2 -b $VM_IMAGE disk

-# Connect our nbd and wait till it is mountable

-qemu-nbd -c $NBD disk

-if ! timeout 60 sh -c "while ! [ -e ${NBD}p1 ]; do sleep 1; done"; then

-    echo "Couldn't connect $NBD"

+# Make sure we have nbd-ness

+modprobe nbd max_part=63

+

+# Set up nbd

+for i in `seq 0 15`; do

+    if [ ! -e /sys/block/nbd$i/pid ]; then

+        NBD=/dev/nbd$i

+        # Connect to nbd and wait till it is ready

+        qemu-nbd -c $NBD disk

+        if ! timeout 60 sh -c "while ! [ -e ${NBD}p1 ]; do sleep 1; done"; then

+            echo "Couldn't connect $NBD"

+            exit 1

+        fi

+        break

+    fi

+done

+if [ -z "$NBD" ]; then

+    echo "No free NBD slots"

     exit 1

 fi

+NBD_DEV=`basename $NBD`

 # Mount the instance

 mount ${NBD}p1 $ROOTFS

@@ -344,9 +352,6 @@ echo "export PS1='${debian_chroot:+($debian_chroot)}\\u@\\H:\\w\\$ '" >> $ROOTFS

 # Give stack ownership over $DEST so it may do the work needed

 chroot $ROOTFS chown -R stack $DEST

-# GRUB 2 wants to see /dev

-mount -o bind /dev $ROOTFS/dev

-

 # Set the hostname

 echo $GUEST_NAME > $ROOTFS/etc/hostname

@@ -355,6 +360,9 @@ if ! grep -q $GUEST_NAME $ROOTFS/etc/hosts; then

     echo "$GUEST_IP $GUEST_NAME" >> $ROOTFS/etc/hosts

 fi

+# GRUB 2 wants to see /dev

+mount -o bind /dev $ROOTFS/dev

+

 # Change boot params so that we get a console log

 G_DEV_UUID=`blkid -t LABEL=cloudimg-rootfs -s UUID -o value | head -1`

 sed -e "s/GRUB_TIMEOUT=.*$/GRUB_TIMEOUT=3/" -i $ROOTFS/etc/default/grub

@@ -51,6 +51,7 @@ fi

 # Default args

 DIST_NAME=$1

 IMG_FILE=$2

+IMG_FILE_TMP=`mktemp $IMG_FILE.XXXXXX`

 case $FORMAT in

     kvm|qcow2)  FORMAT=qcow2

@@ -88,11 +89,6 @@ case $DIST_NAME in

                 ;;

 esac

-# Set up nbd

-modprobe nbd max_part=63

-NBD=${NBD:-/dev/nbd9}

-NBD_DEV=`basename $NBD`

-

 # Prepare the base image

 # Get the UEC image

@@ -103,24 +99,37 @@ fi

 if [ "$FORMAT" = "qcow2" ]; then

     # Just copy image

-    cp -p $CACHEDIR/$UEC_NAME-disk1.img $IMG_FILE

+    cp -p $CACHEDIR/$UEC_NAME-disk1.img $IMG_FILE_TMP

 else

     # Convert image

-    qemu-img convert -O $QFORMAT $CACHEDIR/$UEC_NAME-disk1.img $IMG_FILE

+    qemu-img convert -O $QFORMAT $CACHEDIR/$UEC_NAME-disk1.img $IMG_FILE_TMP

 fi

 # Resize the image if necessary

 if [ $ROOTSIZE -gt 2000 ]; then

     # Resize the container

-    qemu-img resize $IMG_FILE +$((ROOTSIZE - 2000))M

+    qemu-img resize $IMG_FILE_TMP +$((ROOTSIZE - 2000))M

 fi

-# Connect to nbd and wait till it is ready

-qemu-nbd -c $NBD $IMG_FILE

-if ! timeout 60 sh -c "while ! [ -e /sys/block/$NBD_DEV/pid ]; do sleep 1; done"; then

-echo "Couldn't connect $NBD"

+# Set up nbd

+modprobe nbd max_part=63

+for i in `seq 1 15`; do

+    if [ ! -e /sys/block/nbd$i/pid ]; then

+        NBD=/dev/nbd$i

+        # Connect to nbd and wait till it is ready

+        qemu-nbd -c $NBD $IMG_FILE_TMP

+        if ! timeout 60 sh -c "while ! [ -e ${NBD}p1 ]; do sleep 1; done"; then

+            echo "Couldn't connect $NBD"

+            exit 1

+        fi

+        break

+    fi

+done

+if [ -z "$NBD" ]; then

+    echo "No free NBD slots"

     exit 1

 fi

+NBD_DEV=`basename $NBD`

 # Resize partition 1 to full size of the disk image

 echo "d

@@ -153,3 +162,5 @@ rm -f $MNTDIR/etc/resolv.conf

 umount $MNTDIR

 rmdir $MNTDIR

 qemu-nbd -d $NBD

+

+mv $IMG_FILE_TMP $IMG_FILE