diff --git a/scripts/vm/hypervisor/xenserver/check_heartbeat.sh b/scripts/vm/hypervisor/xenserver/check_heartbeat.sh
new file mode 100755
index 00000000000..2f5b40022c3
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/check_heartbeat.sh
@@ -0,0 +1,58 @@
+#!/bin/bash
+
+#set -x
+ 
+usage() {
+  printf "Usage: %s [uuid of this host] [interval in seconds]\n" $(basename $0) >&2
+
+}
+
+if [ -z $1 ]; then
+  usage
+  exit 2
+fi
+
+if [ -z $2 ]; then
+  usage
+  exit 3
+fi
+
+
+date=`date +%s`
+hbs=`lvscan | grep hb-$1 | awk '{print $2}'`
+for hb in $hbs
+do
+  hb=${hb:1:`expr ${#hb} - 2`}
+  active=`lvscan | grep $hb | awk '{print $1}'`
+  if [ "$active" == "inactive" ]; then
+    lvchange -ay $hb
+    if [ ! -L $hb ]; then
+      continue;
+    fi
+  fi
+  ping=`dd if=$hb bs=1 count=100`
+  if [ $? -ne 0 ]; then
+    continue;
+  fi
+  diff=`expr $date - $ping`
+  if [ $diff -lt $2 ]; then
+    echo "=====> ALIVE <====="
+    exit 0;    
+  fi
+done
+
+hbs=`ls -l /var/run/sr-mount/*/hb-$1 | awk '{print $9}'`
+for hb in $hbs
+do
+  ping=`cat $hb`
+  if [ $? -ne 0 ]; then
+    continue;
+  fi
+  diff=`expr $date - $ping`
+  if [ $diff -lt $2 ]; then
+    echo "=====> ALIVE <====="
+    exit 0;    
+  fi
+done
+
+echo "=====> DEAD <======"
diff --git a/scripts/vm/hypervisor/xenserver/copy_vhd_from_secondarystorage.sh b/scripts/vm/hypervisor/xenserver/copy_vhd_from_secondarystorage.sh
new file mode 100755
index 00000000000..5760d5dffe3
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/copy_vhd_from_secondarystorage.sh
@@ -0,0 +1,118 @@
+#!/bin/bash
+
+#set -x
+ 
+usage() {
+  printf "Usage: %s [mountpoint in secondary storage] [uuid of the source sr]\n" $(basename $0) 
+}
+
+cleanup()
+{
+  if [ ! -z $localmp ]; then 
+    umount $localmp
+    if [ $? -eq 0 ];  then
+      rm $localmp -rf
+    fi
+  fi
+}
+
+if [ -z $1 ]; then
+  usage
+  echo "2#no mountpoint"
+  exit 0
+else
+  mountpoint=$1
+fi
+
+if [ -z $2 ]; then
+  usage
+  echo "3#no uuid of the source sr"
+  exit 0
+else
+  sruuid=$2
+fi
+
+type=$(xe sr-param-get uuid=$sruuid param-name=type)
+if [ $? -ne 0 ]; then
+  echo "4#sr $sruuid doesn't exist"
+  exit 0
+fi
+
+localmp=/var/run/cloud_mount/$(uuidgen -r)
+
+mkdir -p $localmp
+if [ $? -ne 0 ]; then
+  echo "5#cann't make dir $localmp"
+  exit 0
+fi
+
+mount $mountpoint $localmp
+if [ $? -ne 0 ]; then
+  echo "6#cann't mounbt $mountpoint to $localmp"
+  exit 0
+fi
+
+vhdfile=$(ls $localmp/*.vhd)
+if [ $? -ne 0 ]; then
+  echo "7#There is no vhd file under $mountpoint"
+  cleanup
+  exit 0
+fi
+
+if [ $type == "nfs" ]; then
+  uuid=$(uuidgen -r)
+  dd if=$vhdfile of=/var/run/sr-mount/$sruuid/$uuid bs=2M
+  if [ $? -ne 0 ]; then
+    echo "8#failed ot copy vhdfile to /var/run/sr-mount/sruuid/$uuid"
+    cleanup
+    exit 0
+  fi
+  mv /var/run/sr-mount/$sruuid/$uuid /var/run/sr-mount/$sruuid/${uuid}.vhd
+  xe sr-scan uuid=$sruuid
+elif [ $type == "lvmoiscsi" -o $type == "lvm" ]; then
+  size=$(vhd-util query -v -n $vhdfile)
+  uuid=$(xe vdi-create sr-uuid=$sruuid virtual-size=${size}MiB type=user name-label="cloud")
+  if [ $? -ne 0 ]; then
+    echo "9#can not create vdi in sr $sruuid"
+    cleanup
+    exit 0
+  fi
+  lvchange -ay /dev/VG_XenStorage-$sruuid/VHD-$uuid
+  if [ $? -ne 0 ]; then
+    echo "10#lvm can not make VDI $uuid  visiable"
+    cleanup
+    exit 0
+  fi
+  dd if=$vhdfile of=/dev/VG_XenStorage-$sruuid/VHD-$uuid bs=2M
+  if [ $? -ne 0 ]; then
+    echo "11#failed to dd to sr $sruuid"
+    cleanup
+    exit 0
+  fi
+  lvsize=$(xe vdi-param-get uuid=$uuid param-name=physical-utilisation)
+  if [ $? -ne 0 ]; then
+    echo "12#failed to get physical size of vdi $uuid"
+    cleanup
+    exit 0
+  fi
+  vhd-util modify -s $lvsize -n /dev/VG_XenStorage-$sruuid/VHD-$uuid
+  if [ $? -ne 0 ]; then
+    echo "13#failed to set new vhd physical size for vdi vdi $uuid"
+    cleanup
+    exit 0
+  fi
+  xe sr-scan uuid=$sruuid
+  if [ $? -ne 0 ]; then
+    echo "14#failed to scan sr $sruuid"
+    cleanup
+    exit 0
+  fi
+else 
+  echo "15#doesn't support sr type $type"
+  cleanup
+  exit 0
+fi
+
+echo "0#$uuid"
+cleanup
+exit 0
diff --git a/scripts/vm/hypervisor/xenserver/copy_vhd_to_secondarystorage.sh b/scripts/vm/hypervisor/xenserver/copy_vhd_to_secondarystorage.sh
new file mode 100755
index 00000000000..65800dbe994
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/copy_vhd_to_secondarystorage.sh
@@ -0,0 +1,106 @@
+#!/bin/bash
+
+#set -x
+ 
+usage() {
+  printf "Usage: %s [mountpoint in secondary storage] [uuid of the source vdi] [uuid of the source sr]\n" $(basename $0) 
+}
+
+cleanup()
+{
+  if [ ! -z $localmp ]; then 
+    umount $localmp
+    if [ $? -eq 0 ];  then
+      rm $localmp -rf
+    fi
+  fi
+}
+
+if [ -z $1 ]; then
+  usage
+  echo "1#no mountpoint"
+  exit 0
+else
+  mountpoint=$1
+fi
+
+if [ -z $2 ]; then
+  usage
+  echo "2#no uuid of the source sr"
+  exit 0
+else
+  vdiuuid=$2
+fi
+
+
+if [ -z $3 ]; then
+  usage
+  echo "3#no uuid of the source sr"
+  exit 0
+else
+  sruuid=$3
+fi
+
+type=$(xe sr-param-get uuid=$sruuid param-name=type)
+if [ $? -ne 0 ]; then
+  echo "4#sr $sruuid doesn't exist"
+  exit 0
+fi
+
+localmp=/var/run/cloud_mount/$(uuidgen -r)
+
+mkdir -p $localmp
+if [ $? -ne 0 ]; then
+  echo "5#cann't make dir $localmp"
+  exit 0
+fi
+
+mount $mountpoint $localmp
+if [ $? -ne 0 ]; then
+  echo "6#cann't mounbt $mountpoint to $localmp"
+  exit 0
+fi
+
+vhdfile=$localmp/${vdiuuid}.vhd
+
+if [ $type == "nfs" ]; then
+  dd if=/var/run/sr-mount/$sruuid/${vdiuuid}.vhd of=$vhdfile bs=2M
+  if [ $? -ne 0 ]; then
+    echo "8#failed to copy /var/run/sr-mount/$sruuid/${vdiuuid}.vhd to secondarystorage"
+    cleanup
+    exit 0
+  fi
+elif [ $type == "lvmoiscsi" -o $type == "lvm" ]; then
+  lvchange -ay /dev/VG_XenStorage-$sruuid/VHD-$vdiuuid
+  if [ $? -ne 0 ]; then
+    echo "9#lvm can not make VDI $vdiuuid  visiable"
+    cleanup
+    exit 0
+  fi
+  size=$(vhd-util query -s -n /dev/VG_XenStorage-$sruuid/VHD-$vdiuuid)
+  if [ $? -ne 0 ]; then
+    echo "10#can not get physical size of /dev/VG_XenStorage-$sruuid/VHD-$vdiuuid"
+    cleanup
+    exit 0
+  fi
+#in 2M unit
+  size=$((size>>21))
+  size=$((size+1))
+  dd if=/dev/VG_XenStorage-$sruuid/VHD-$vdiuuid of=$vhdfile bs=2M count=$size
+#in byte unit
+  size=$((size<<21))
+  vhd-util modify -s $size -n $vhdfile
+  if [ $? -ne 0 ]; then
+    echo "11#failed to change $vhdfile physical size"
+    cleanup
+    exit 0
+  fi
+else 
+  echo "15#doesn't support sr type $type"
+  cleanup
+  exit 0
+fi
+
+echo "0#$vdiuuid"
+cleanup
+exit 0
diff --git a/scripts/vm/hypervisor/xenserver/fsimage.so b/scripts/vm/hypervisor/xenserver/fsimage.so
new file mode 100755
index 00000000000..05e0d041d91
Binary files /dev/null and b/scripts/vm/hypervisor/xenserver/fsimage.so differ
diff --git a/scripts/vm/hypervisor/xenserver/launch_hb.sh b/scripts/vm/hypervisor/xenserver/launch_hb.sh
new file mode 100755
index 00000000000..b2b4b994528
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/launch_hb.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+
+#set -x
+ 
+usage() {
+  printf "Usage: %s [uuid of this host] [interval in seconds]\n" $(basename $0)
+
+}
+
+if [ -z $1 ]; then
+  usage
+  exit 2
+fi
+
+if [ -z $2 ]; then
+  usage
+  exit 3
+fi
+
+if [ ! -f /opt/xensource/bin/xenheartbeat.sh ]; then
+  printf "Error: Unable to find xenheartbeat.sh to launch\n"
+  exit 4
+fi
+
+for psid in `ps -ef | grep xenheartbeat | grep -v grep | awk '{print $2}'`; do
+  kill $psid
+done
+
+nohup /opt/xensource/bin/xenheartbeat.sh $1 $2 >/dev/null 2>/dev/null &
+echo "======> DONE <======"
diff --git a/scripts/vm/hypervisor/xenserver/setupXenServer.sh b/scripts/vm/hypervisor/xenserver/setupXenServer.sh
new file mode 100755
index 00000000000..78743d644ca
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/setupXenServer.sh
@@ -0,0 +1,13 @@
+#!/bin/bash
+
+# avoid disk full
+mv /etc/cron.daily/logrotate /etc/cron.hourly 2>&1
+
+# more aio thread
+echo 1048576 >/proc/sys/fs/aio-max-nr
+
+# empty heartbeat
+cat /dev/null > /opt/xensource/bin/heartbeat
+
+echo "success"
+
diff --git a/scripts/vm/hypervisor/xenserver/setup_heartbeat_file.sh b/scripts/vm/hypervisor/xenserver/setup_heartbeat_file.sh
new file mode 100755
index 00000000000..42ff965e5be
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/setup_heartbeat_file.sh
@@ -0,0 +1,72 @@
+#!/bin/bash
+
+#set -x
+
+usage() {
+  printf "Usage: %s [uuid of this host] [uuid of the sr to place the heartbeat]\n" $(basename $0)
+
+}
+
+
+if [ -z $1 ]; then
+  usage
+  echo "1# no uuid of host"
+  exit 0
+fi
+
+if [ -z $2 ]; then
+  usage
+  echo "2# no uuid of sr"
+  exit 0
+fi
+
+if [ `xe host-list | grep $1 | wc -l` -ne 1 ]; then
+  echo  "3# Unable to find the host uuid: $1"
+  exit 0
+fi
+
+if [ `xe sr-list uuid=$2 | wc -l`  -eq 0 ]; then 
+  echo "4# Unable to find SR with uuid: $2"
+  exit 0
+fi
+
+if [ `xe pbd-list sr-uuid=$2 | grep -B 1 $1 | wc -l` -eq 0 ]; then
+  echo "5# Unable to find a pbd for the SR: $2"
+  exit 0
+fi
+
+srtype=`xe sr-param-get param-name=type uuid=$2`
+
+ 
+if [ "$srtype" = "nfs" ];then
+  dir=/var/run/sr-mount/$2
+  filename=$dir/hb-$1
+  if [ ! -f "$filename" ]; then
+    echo "6# heartbeat file $filename doesn't exist"
+    exit 0
+  fi
+else 
+  dir=/dev/VG_XenStorage-$2
+  link=$dir/hb-$1
+  lvchange -ay $link
+  if [ $? -ne 0 ]; then
+     echo "7# Unable to make the heartbeat $link active"
+     exit 0
+  fi
+fi
+
+hbfile=/opt/xensource/bin/heartbeat
+
+if [ -f $hbfile ]; then
+  grep $dir $hbfile >/dev/null
+  if [ $? -gt 0 ]
+  then
+    echo $dir >> $hbfile
+  fi
+else
+  echo $dir >> $hbfile
+fi
+ 
+echo "0#DONE"
+
+exit 0
diff --git a/scripts/vm/hypervisor/xenserver/setup_heartbeat_sr.sh b/scripts/vm/hypervisor/xenserver/setup_heartbeat_sr.sh
new file mode 100755
index 00000000000..0408c417e90
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/setup_heartbeat_sr.sh
@@ -0,0 +1,88 @@
+#!/bin/bash
+
+#set -x
+ 
+usage() {
+  echo "Usage: $(basename $0) [uuid of this host] [uuid of the sr to place the heartbeat]"
+
+}
+
+if [ -z $1 ]; then
+  usage
+  echo "1#no host uuid"
+  exit 0
+fi
+
+if [ -z $2 ]; then
+  usage
+  echo "2#no sr uuid"
+  exit 0
+fi
+
+if [ `xe host-list | grep $1 | wc -l` -ne 1 ]; then
+  echo  "3# Unable to find the host uuid: $1"
+  exit 0
+fi
+
+if [ `xe sr-list uuid=$2 | wc -l`  -eq 0 ]; then 
+  echo "4# Unable to find SR with uuid: $2"
+  exit 0
+fi
+
+if [ `xe pbd-list sr-uuid=$2 | grep -B 1 $1 | wc -l` -eq 0 ]; then
+  echo "5# Unable to find a pbd for the SR: $2"
+  exit 0
+fi
+
+srtype=`xe sr-param-get param-name=type uuid=$2`
+
+if [ "$srtype" == "nfs" ];then
+  dir=/var/run/sr-mount/$2
+  filename=$dir/hb-$1
+  files=`ls $dir | grep "hb-$1"`
+  if [ -z "$files" ]; then
+    date=`date +%s`
+    echo "$date" > $filename
+  fi
+else 
+  dir=/dev/VG_XenStorage-$2
+  link=$dir/hb-$1
+  lv=`lvscan | grep $link`
+  if [ -z "$lv" ]; then
+    if [ -e $link ]; then
+      devmapper=$(ls $link -l | awk '{print $NF}')
+      if [ -e $devmapper ]; then
+        dmsetup remove -f $devmapper
+      fi
+      rm $link -f
+    fi 
+    lvcreate VG_XenStorage-$2 -n hb-$1 --size 4M
+    if [ $? -ne 0 ]; then
+      echo "6# Unable to create heartbeat volume hb-$1"
+      exit 0
+    fi
+    lv=`lvscan | grep $link`
+    if [ -z "$lv" ]; then
+      echo "7# volume hb-$1 is not created"
+      exit 0
+    fi
+  fi
+
+  if [ `echo $lv | awk '{print $1}'` == "inactive" ]; then
+    lvchange -ay $link
+    if [ $? -ne 0 ]; then
+      echo "8# Unable to make $link active"
+      exit 0
+    fi
+  fi
+
+  if [ ! -L $link ]; then
+    echo "9# Unable to find the soft link $link"
+    exit 0
+  fi
+  dd if=/dev/zero of=$link bs=1 count=100
+fi
+
+echo "0#DONE"
+
+exit 0
diff --git a/scripts/vm/hypervisor/xenserver/vmopspremium b/scripts/vm/hypervisor/xenserver/vmopspremium
new file mode 100755
index 00000000000..5fada9eb5f9
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/vmopspremium
@@ -0,0 +1,101 @@
+#!/usr/bin/python
+#
+# A plugin for executing script needed by vmops cloud 
+
+import os, sys, time
+import XenAPIPlugin
+sys.path.append("/opt/xensource/sm/")
+import util
+import socket
+
+def echo(fn):
+    def wrapped(*v, **k):
+        name = fn.__name__
+        util.SMlog("#### VMOPS enter  %s ####" % name )
+        res = fn(*v, **k)
+        util.SMlog("#### VMOPS exit  %s ####" % name )
+        return res
+    return wrapped
+
+@echo
+def copy_vhd_to_secondarystorage(session, args):
+    mountpoint = args['mountpoint']
+    vdiuuid = args['vdiuuid']
+    sruuid = args['sruuid']
+    try:
+        cmd = ["bash", "/opt/xensource/bin/copy_vhd_to_secondarystorage.sh", mountpoint, vdiuuid, sruuid]
+        txt = util.pread2(cmd)
+    except:
+        txt = '10#failed'
+    return txt
+
+@echo
+def copy_vhd_from_secondarystorage(session, args):
+    mountpoint = args['mountpoint']
+    sruuid = args['sruuid']
+    try:
+        cmd = ["bash", "/opt/xensource/bin/copy_vhd_from_secondarystorage.sh", mountpoint, sruuid]
+        txt = util.pread2(cmd)
+    except:
+        txt = '10#failed'
+    return txt
+
+@echo
+def setup_heartbeat_sr(session, args):
+    host = args['host']
+    sr = args['sr']
+    try:
+        cmd = ["bash", "/opt/xensource/bin/setup_heartbeat_sr.sh", host, sr]
+        txt = util.pread2(cmd)
+    except:
+        txt = ''
+    return txt
+
+@echo
+def setup_heartbeat_file(session, args):
+    host = args['host']
+    sr = args['sr']
+    try:
+        cmd = ["bash", "/opt/xensource/bin/setup_heartbeat_file.sh", host, sr]
+        txt = util.pread2(cmd)
+    except:
+        txt = ''
+    return txt
+
+@echo
+def check_heartbeat(session, args):
+    host = args['host']
+    interval = args['interval']
+    try:
+       cmd = ["bash", "/opt/xensource/bin/check_heartbeat.sh", host, interval]
+       txt = util.pread2(cmd)
+    except:
+       txt=''
+    return txt
+    
+   
+@echo
+def heartbeat(session, args):
+    host = args['host']
+    interval = args['interval']
+    try: 
+       cmd = ["/bin/bash", "/opt/xensource/bin/launch_hb.sh", host, interval]
+       txt = util.pread2(cmd)
+    except:
+       txt='fail'
+    return txt
+
+
+@echo
+def setupXenServer(session, args):
+    try:
+        cmd = ["/bin/bash", "/opt/xensource/bin/setupXenServer.sh"]
+        txt = util.pread2(cmd)
+        return txt
+    except:
+        raise xs_errors.XenError('setupXenServer.sh execution failed.')
+
+
+if __name__ == "__main__":
+    XenAPIPlugin.dispatch({"copy_vhd_to_secondarystorage":copy_vhd_to_secondarystorage, "copy_vhd_from_secondarystorage":copy_vhd_from_secondarystorage, "setup_heartbeat_sr":setup_heartbeat_sr, "setup_heartbeat_file":setup_heartbeat_file, "check_heartbeat":check_heartbeat, "heartbeat": heartbeat, "setupXenServer":setupXenServer})
+
diff --git a/scripts/vm/hypervisor/xenserver/xenheartbeat.sh b/scripts/vm/hypervisor/xenserver/xenheartbeat.sh
new file mode 100755
index 00000000000..2ba79a21b12
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/xenheartbeat.sh
@@ -0,0 +1,64 @@
+#!/bin/bash
+# Version @VERSION@
+
+#set -x
+ 
+usage() {
+  printf "Usage: %s [uuid of this host] [interval in seconds]\n" $(basename $0) >&2
+
+}
+
+if [ -z $1 ]; then
+  usage
+  exit 2
+fi
+
+if [ -z $2 ]; then
+  usage
+  exit 3
+fi
+
+file=/opt/xensource/bin/heartbeat
+while true 
+do 
+  sleep $2
+
+  if [ ! -f $file  ]
+  then
+    continue
+  fi
+
+  # for iscsi
+  dirs=$(cat $file | grep VG_XenStorage)
+  for dir in $dirs
+  do
+    if [ -d $dir ]; then
+      hb=$dir/hb-$1
+      date +%s | dd of=$hb count=100 bs=1 2>/dev/null
+      if [ $? -ne 0 ]; then
+          /usr/bin/logger -t heartbeat "Problem with $hb"
+          reboot -f
+      fi
+    else
+      sed -i /${dir##/*/}/d $file
+    fi
+  done
+  # for nfs
+  dirs=$(cat $file | grep sr-mount)
+  for dir in $dirs
+  do
+    mp=`mount | grep $dir`
+    if [ -n "$mp" ]; then
+      hb=$dir/hb-$1
+      date +%s | dd of=$hb count=100 bs=1 2>/dev/null
+      if [ $? -ne 0 ]; then
+          /usr/bin/logger -t heartbeat "Problem with $hb"
+          reboot -f
+      fi
+    else
+      sed -i /${dir##/*/}/d $file
+    fi
+  done
+
+done
+
diff --git a/scripts/vm/hypervisor/xenserver/xenserver56/InterfaceReconfigure.py b/scripts/vm/hypervisor/xenserver/xenserver56/InterfaceReconfigure.py
new file mode 100755
index 00000000000..9723c6617eb
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/xenserver56/InterfaceReconfigure.py
@@ -0,0 +1,870 @@
+# Copyright (c) 2008,2009 Citrix Systems, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published
+# by the Free Software Foundation; version 2.1 only. with the special
+# exception on linking described in file LICENSE.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+import sys
+import syslog
+import os
+
+from xml.dom.minidom import getDOMImplementation
+from xml.dom.minidom import parse as parseXML
+
+the_root_prefix = ""
+def root_prefix():
+    """Returns a string to prefix to all file name references, which
+    is useful for testing."""
+    return the_root_prefix
+def set_root_prefix(prefix):
+    global the_root_prefix
+    the_root_prefix = prefix
+
+log_destination = "syslog"
+def get_log_destination():
+    """Returns the current log destination.
+    'syslog' means "log to syslog".
+    'stderr' means "log to stderr"."""
+    return log_destination
+def set_log_destination(dest):
+    global log_destination
+    log_destination = dest
+
+#
+# Logging.
+#
+
+def log(s):
+    if get_log_destination() == 'syslog':
+        syslog.syslog(s)
+    else:
+        print >>sys.stderr, s
+
+#
+# Exceptions.
+#
+
+class Error(Exception):
+    def __init__(self, msg):
+        Exception.__init__(self)
+        self.msg = msg
+
+#
+# Run external utilities
+#
+
+def run_command(command):
+    log("Running command: " + ' '.join(command))
+    rc = os.spawnl(os.P_WAIT, root_prefix() + command[0], *command)
+    if rc != 0:
+        log("Command failed %d: " % rc + ' '.join(command))
+        return False
+    return True
+
+#
+# Configuration File Handling.
+#
+
+class ConfigurationFile(object):
+    """Write a file, tracking old and new versions.
+
+    Supports writing a new version of a file and applying and
+    reverting those changes.
+    """
+
+    __STATE = {"OPEN":"OPEN",
+               "NOT-APPLIED":"NOT-APPLIED", "APPLIED":"APPLIED",
+               "REVERTED":"REVERTED", "COMMITTED": "COMMITTED"}
+
+    def __init__(self, path):
+        dirname,basename = os.path.split(path)
+
+        self.__state = self.__STATE['OPEN']
+        self.__children = []
+
+        self.__path    = os.path.join(dirname, basename)
+        self.__oldpath = os.path.join(dirname, "." + basename + ".xapi-old")
+        self.__newpath = os.path.join(dirname, "." + basename + ".xapi-new")
+
+        self.__f = open(self.__newpath, "w")
+
+    def attach_child(self, child):
+        self.__children.append(child)
+
+    def path(self):
+        return self.__path
+
+    def readlines(self):
+        try:
+            return open(self.path()).readlines()
+        except:
+            return ""
+
+    def write(self, args):
+        if self.__state != self.__STATE['OPEN']:
+            raise Error("Attempt to write to file in state %s" % self.__state)
+        self.__f.write(args)
+
+    def close(self):
+        if self.__state != self.__STATE['OPEN']:
+            raise Error("Attempt to close file in state %s" % self.__state)
+
+        self.__f.close()
+        self.__state = self.__STATE['NOT-APPLIED']
+
+    def changed(self):
+        if self.__state != self.__STATE['NOT-APPLIED']:
+            raise Error("Attempt to compare file in state %s" % self.__state)
+
+        return True
+
+    def apply(self):
+        if self.__state != self.__STATE['NOT-APPLIED']:
+            raise Error("Attempt to apply configuration from state %s" % self.__state)
+
+        for child in self.__children:
+            child.apply()
+
+        log("Applying changes to %s configuration" % self.__path)
+
+        # Remove previous backup.
+        if os.access(self.__oldpath, os.F_OK):
+            os.unlink(self.__oldpath)
+
+        # Save current configuration.
+        if os.access(self.__path, os.F_OK):
+            os.link(self.__path, self.__oldpath)
+            os.unlink(self.__path)
+
+        # Apply new configuration.
+        assert(os.path.exists(self.__newpath))
+        os.link(self.__newpath, self.__path)
+
+        # Remove temporary file.
+        os.unlink(self.__newpath)
+
+        self.__state = self.__STATE['APPLIED']
+
+    def revert(self):
+        if self.__state != self.__STATE['APPLIED']:
+            raise Error("Attempt to revert configuration from state %s" % self.__state)
+
+        for child in self.__children:
+            child.revert()
+
+        log("Reverting changes to %s configuration" % self.__path)
+
+        # Remove existing new configuration
+        if os.access(self.__newpath, os.F_OK):
+            os.unlink(self.__newpath)
+
+        # Revert new configuration.
+        if os.access(self.__path, os.F_OK):
+            os.link(self.__path, self.__newpath)
+            os.unlink(self.__path)
+
+        # Revert to old configuration.
+        if os.access(self.__oldpath, os.F_OK):
+            os.link(self.__oldpath, self.__path)
+            os.unlink(self.__oldpath)
+
+        # Leave .*.xapi-new as an aid to debugging.
+
+        self.__state = self.__STATE['REVERTED']
+
+    def commit(self):
+        if self.__state != self.__STATE['APPLIED']:
+            raise Error("Attempt to commit configuration from state %s" % self.__state)
+
+        for child in self.__children:
+            child.commit()
+
+        log("Committing changes to %s configuration" % self.__path)
+
+        if os.access(self.__oldpath, os.F_OK):
+            os.unlink(self.__oldpath)
+        if os.access(self.__newpath, os.F_OK):
+            os.unlink(self.__newpath)
+
+        self.__state = self.__STATE['COMMITTED']
+
+#
+# Helper functions for encoding/decoding database attributes to/from XML.
+#
+
+def _str_to_xml(xml, parent, tag, val):
+    e = xml.createElement(tag)
+    parent.appendChild(e)
+    v = xml.createTextNode(val)
+    e.appendChild(v)
+def _str_from_xml(n):
+    def getText(nodelist):
+        rc = ""
+        for node in nodelist:
+            if node.nodeType == node.TEXT_NODE:
+                rc = rc + node.data
+        return rc
+    return getText(n.childNodes).strip()
+
+def _bool_to_xml(xml, parent, tag, val):
+    if val:
+        _str_to_xml(xml, parent, tag, "True")
+    else:
+        _str_to_xml(xml, parent, tag, "False")
+def _bool_from_xml(n):
+    s = _str_from_xml(n)
+    if s == "True":
+        return True
+    elif s == "False":
+        return False
+    else:
+        raise Error("Unknown boolean value %s" % s)
+
+def _strlist_to_xml(xml, parent, ltag, itag, val):
+    e = xml.createElement(ltag)
+    parent.appendChild(e)
+    for v in val:
+        c = xml.createElement(itag)
+        e.appendChild(c)
+        cv = xml.createTextNode(v)
+        c.appendChild(cv)
+def _strlist_from_xml(n, ltag, itag):
+    ret = []
+    for n in n.childNodes:
+        if n.nodeName == itag:
+            ret.append(_str_from_xml(n))
+    return ret
+
+def _otherconfig_to_xml(xml, parent, val, attrs):
+    otherconfig = xml.createElement("other_config")
+    parent.appendChild(otherconfig)
+    for n,v in val.items():
+        if not n in attrs:
+            raise Error("Unknown other-config attribute: %s" % n)
+        _str_to_xml(xml, otherconfig, n, v)
+def _otherconfig_from_xml(n, attrs):
+    ret = {}
+    for n in n.childNodes:
+        if n.nodeName in attrs:
+            ret[n.nodeName] = _str_from_xml(n)
+    return ret
+
+#
+# Definitions of the database objects (and their attributes) used by interface-reconfigure.
+#
+# Each object is defined by a dictionary mapping an attribute name in
+# the xapi database to a tuple containing two items:
+#  - a function which takes this attribute and encodes it as XML.
+#  - a function which takes XML and decocdes it into a value.
+#
+# other-config attributes are specified as a simple array of strings
+
+_PIF_XML_TAG = "pif"
+_VLAN_XML_TAG = "vlan"
+_BOND_XML_TAG = "bond"
+_NETWORK_XML_TAG = "network"
+
+_ETHTOOL_OTHERCONFIG_ATTRS = ['ethtool-%s' % x for x in 'autoneg', 'speed', 'duplex', 'rx', 'tx', 'sg', 'tso', 'ufo', 'gso' ]
+
+_PIF_OTHERCONFIG_ATTRS = [ 'domain', 'peerdns', 'defaultroute', 'mtu', 'static-routes' ] + \
+                        [ 'bond-%s' % x for x in 'mode', 'miimon', 'downdelay', 'updelay', 'use_carrier' ] + \
+                        _ETHTOOL_OTHERCONFIG_ATTRS
+
+_PIF_ATTRS = { 'uuid': (_str_to_xml,_str_from_xml),
+               'management': (_bool_to_xml,_bool_from_xml),
+               'network': (_str_to_xml,_str_from_xml),
+               'device': (_str_to_xml,_str_from_xml),
+               'bond_master_of': (lambda x, p, t, v: _strlist_to_xml(x, p, 'bond_master_of', 'slave', v),
+                                  lambda n: _strlist_from_xml(n, 'bond_master_of', 'slave')),
+               'bond_slave_of': (_str_to_xml,_str_from_xml),
+               'VLAN': (_str_to_xml,_str_from_xml),
+               'VLAN_master_of': (_str_to_xml,_str_from_xml),
+               'VLAN_slave_of': (lambda x, p, t, v: _strlist_to_xml(x, p, 'VLAN_slave_of', 'master', v),
+                                 lambda n: _strlist_from_xml(n, 'VLAN_slave_Of', 'master')),
+               'ip_configuration_mode': (_str_to_xml,_str_from_xml),
+               'IP': (_str_to_xml,_str_from_xml),
+               'netmask': (_str_to_xml,_str_from_xml),
+               'gateway': (_str_to_xml,_str_from_xml),
+               'DNS': (_str_to_xml,_str_from_xml),
+               'MAC': (_str_to_xml,_str_from_xml),
+               'other_config': (lambda x, p, t, v: _otherconfig_to_xml(x, p, v, _PIF_OTHERCONFIG_ATTRS),
+                                lambda n: _otherconfig_from_xml(n, _PIF_OTHERCONFIG_ATTRS)),
+
+               # Special case: We write the current value
+               # PIF.currently-attached to the cache but since it will
+               # not be valid when we come to use the cache later
+               # (i.e. after a reboot) we always read it as False.
+               'currently_attached': (_bool_to_xml, lambda n: False),
+             }
+
+_VLAN_ATTRS = { 'uuid': (_str_to_xml,_str_from_xml),
+                'tagged_PIF': (_str_to_xml,_str_from_xml),
+                'untagged_PIF': (_str_to_xml,_str_from_xml),
+              }
+
+_BOND_ATTRS = { 'uuid': (_str_to_xml,_str_from_xml),
+               'master': (_str_to_xml,_str_from_xml),
+               'slaves': (lambda x, p, t, v: _strlist_to_xml(x, p, 'slaves', 'slave', v),
+                          lambda n: _strlist_from_xml(n, 'slaves', 'slave')),
+              }
+
+_NETWORK_OTHERCONFIG_ATTRS = [ 'mtu', 'static-routes' ] + _ETHTOOL_OTHERCONFIG_ATTRS
+
+_NETWORK_ATTRS = { 'uuid': (_str_to_xml,_str_from_xml),
+                   'bridge': (_str_to_xml,_str_from_xml),
+                   'MTU': (_str_to_xml,_str_from_xml),
+                   'PIFs': (lambda x, p, t, v: _strlist_to_xml(x, p, 'PIFs', 'PIF', v),
+                            lambda n: _strlist_from_xml(n, 'PIFs', 'PIF')),
+                   'other_config': (lambda x, p, t, v: _otherconfig_to_xml(x, p, v, _NETWORK_OTHERCONFIG_ATTRS),
+                                    lambda n: _otherconfig_from_xml(n, _NETWORK_OTHERCONFIG_ATTRS)),
+                 }
+
+#
+# Database Cache object
+#
+
+_db = None
+
+def db():
+    assert(_db is not None)
+    return _db
+
+def db_init_from_cache(cache):
+    global _db
+    assert(_db is None)
+    _db = DatabaseCache(cache_file=cache)
+    
+def db_init_from_xenapi(session):
+    global _db 
+    assert(_db is None)
+    _db  = DatabaseCache(session_ref=session)
+    
+class DatabaseCache(object):
+    def __read_xensource_inventory(self):
+        filename = root_prefix() + "/etc/xensource-inventory"
+        f = open(filename, "r")
+        lines = [x.strip("\n") for x in f.readlines()]
+        f.close()
+
+        defs = [ (l[:l.find("=")], l[(l.find("=") + 1):]) for l in lines ]
+        defs = [ (a, b.strip("'")) for (a,b) in defs ]
+
+        return dict(defs)
+
+    def __pif_on_host(self,pif):
+        return self.__pifs.has_key(pif)
+
+    def __get_pif_records_from_xapi(self, session, host):
+        self.__pifs = {}
+        for (p,rec) in session.xenapi.PIF.get_all_records().items():
+            if rec['host'] != host:
+                continue
+            self.__pifs[p] = {}
+            for f in _PIF_ATTRS:
+                self.__pifs[p][f] = rec[f]
+            self.__pifs[p]['other_config'] = {}
+            for f in _PIF_OTHERCONFIG_ATTRS:
+                if not rec['other_config'].has_key(f): continue
+                self.__pifs[p]['other_config'][f] = rec['other_config'][f]
+
+    def __get_vlan_records_from_xapi(self, session):
+        self.__vlans = {}
+        for v in session.xenapi.VLAN.get_all():
+            rec = session.xenapi.VLAN.get_record(v)
+            if not self.__pif_on_host(rec['untagged_PIF']):
+                continue
+            self.__vlans[v] = {}
+            for f in _VLAN_ATTRS:
+                self.__vlans[v][f] = rec[f]
+
+    def __get_bond_records_from_xapi(self, session):
+        self.__bonds = {}
+        for b in session.xenapi.Bond.get_all():
+            rec = session.xenapi.Bond.get_record(b)
+            if not self.__pif_on_host(rec['master']):
+                continue
+            self.__bonds[b] = {}
+            for f in _BOND_ATTRS:
+                self.__bonds[b][f] = rec[f]
+
+    def __get_network_records_from_xapi(self, session):
+        self.__networks = {}
+        for n in session.xenapi.network.get_all():
+            rec = session.xenapi.network.get_record(n)
+            self.__networks[n] = {}
+            for f in _NETWORK_ATTRS:
+                if f == "PIFs":
+                    # drop PIFs on other hosts
+                    self.__networks[n][f] = [p for p in rec[f] if self.__pif_on_host(p)]
+                elif f == "MTU" and f not in rec:
+                    # XenServer 5.5 network records did not have an
+                    # MTU field, so allow this to be missing.
+                    pass
+                else:
+                    self.__networks[n][f] = rec[f]
+            self.__networks[n]['other_config'] = {}
+            for f in _NETWORK_OTHERCONFIG_ATTRS:
+                if not rec['other_config'].has_key(f): continue
+                self.__networks[n]['other_config'][f] = rec['other_config'][f]
+
+    def __to_xml(self, xml, parent, key, ref, rec, attrs):
+        """Encode a database object as XML"""
+        e = xml.createElement(key)
+        parent.appendChild(e)
+        if ref:
+            e.setAttribute('ref', ref)
+
+        for n,v in rec.items():
+            if attrs.has_key(n):
+                h,_ = attrs[n]
+                h(xml, e, n, v)
+            else:
+                raise Error("Unknown attribute %s" % n)
+    def __from_xml(self, e, attrs):
+        """Decode a database object from XML"""
+        ref = e.attributes['ref'].value
+        rec = {}
+        for n in e.childNodes:
+            if n.nodeName in attrs:
+                _,h = attrs[n.nodeName]
+                rec[n.nodeName] = h(n)
+        return (ref,rec)
+
+    def __init__(self, session_ref=None, cache_file=None):
+        if session_ref and cache_file:
+            raise Error("can't specify session reference and cache file")
+        if cache_file == None:
+            import XenAPI
+            session = XenAPI.xapi_local()
+
+            if not session_ref:
+                log("No session ref given on command line, logging in.")
+                session.xenapi.login_with_password("root", "")
+            else:
+                session._session = session_ref
+
+            try:
+
+                inventory = self.__read_xensource_inventory()
+                assert(inventory.has_key('INSTALLATION_UUID'))
+                log("host uuid is %s" % inventory['INSTALLATION_UUID'])
+
+                host = session.xenapi.host.get_by_uuid(inventory['INSTALLATION_UUID'])
+
+                self.__get_pif_records_from_xapi(session, host)
+
+                self.__get_vlan_records_from_xapi(session)
+                self.__get_bond_records_from_xapi(session)
+                self.__get_network_records_from_xapi(session)
+            finally:
+                if not session_ref:
+                    session.xenapi.session.logout()
+        else:
+            log("Loading xapi database cache from %s" % cache_file)
+
+            xml = parseXML(root_prefix() + cache_file)
+
+            self.__pifs = {}
+            self.__bonds = {}
+            self.__vlans = {}
+            self.__networks = {}
+
+            assert(len(xml.childNodes) == 1)
+            toplevel = xml.childNodes[0]
+
+            assert(toplevel.nodeName == "xenserver-network-configuration")
+
+            for n in toplevel.childNodes:
+                if n.nodeName == "#text":
+                    pass
+                elif n.nodeName == _PIF_XML_TAG:
+                    (ref,rec) = self.__from_xml(n, _PIF_ATTRS)
+                    self.__pifs[ref] = rec
+                elif n.nodeName == _BOND_XML_TAG:
+                    (ref,rec) = self.__from_xml(n, _BOND_ATTRS)
+                    self.__bonds[ref] = rec
+                elif n.nodeName == _VLAN_XML_TAG:
+                    (ref,rec) = self.__from_xml(n, _VLAN_ATTRS)
+                    self.__vlans[ref] = rec
+                elif n.nodeName == _NETWORK_XML_TAG:
+                    (ref,rec) = self.__from_xml(n, _NETWORK_ATTRS)
+                    self.__networks[ref] = rec
+                else:
+                    raise Error("Unknown XML element %s" % n.nodeName)
+
+    def save(self, cache_file):
+
+        xml = getDOMImplementation().createDocument(
+            None, "xenserver-network-configuration", None)
+        for (ref,rec) in self.__pifs.items():
+            self.__to_xml(xml, xml.documentElement, _PIF_XML_TAG, ref, rec, _PIF_ATTRS)
+        for (ref,rec) in self.__bonds.items():
+            self.__to_xml(xml, xml.documentElement, _BOND_XML_TAG, ref, rec, _BOND_ATTRS)
+        for (ref,rec) in self.__vlans.items():
+            self.__to_xml(xml, xml.documentElement, _VLAN_XML_TAG, ref, rec, _VLAN_ATTRS)
+        for (ref,rec) in self.__networks.items():
+            self.__to_xml(xml, xml.documentElement, _NETWORK_XML_TAG, ref, rec,
+                          _NETWORK_ATTRS)
+
+        f = open(cache_file, 'w')
+        f.write(xml.toprettyxml())
+        f.close()
+
+    def get_pif_by_uuid(self, uuid):
+        pifs = map(lambda (ref,rec): ref,
+                  filter(lambda (ref,rec): uuid == rec['uuid'],
+                         self.__pifs.items()))
+        if len(pifs) == 0:
+            raise Error("Unknown PIF \"%s\"" % uuid)
+        elif len(pifs) > 1:
+            raise Error("Non-unique PIF \"%s\"" % uuid)
+
+        return pifs[0]
+
+    def get_pifs_by_device(self, device):
+        return map(lambda (ref,rec): ref,
+                   filter(lambda (ref,rec): rec['device'] == device,
+                          self.__pifs.items()))
+
+    def get_pif_by_bridge(self, bridge):
+        networks = map(lambda (ref,rec): ref,
+                       filter(lambda (ref,rec): rec['bridge'] == bridge,
+                              self.__networks.items()))
+        if len(networks) == 0:
+            raise Error("No matching network \"%s\"" % bridge)
+
+        answer = None
+        for network in networks:
+            nwrec = self.get_network_record(network)
+            for pif in nwrec['PIFs']:
+                pifrec = self.get_pif_record(pif)
+                if answer:
+                    raise Error("Multiple PIFs on host for network %s" % (bridge))
+                answer = pif
+        if not answer:
+            raise Error("No PIF on host for network %s" % (bridge))
+        return answer
+
+    def get_pif_record(self, pif):
+        if self.__pifs.has_key(pif):
+            return self.__pifs[pif]
+        raise Error("Unknown PIF \"%s\"" % pif)
+    def get_all_pifs(self):
+        return self.__pifs
+    def pif_exists(self, pif):
+        return self.__pifs.has_key(pif)
+
+    def get_management_pif(self):
+        """ Returns the management pif on host
+        """
+        all = self.get_all_pifs()
+        for pif in all:
+            pifrec = self.get_pif_record(pif)
+            if pifrec['management']: return pif
+        return None
+
+    def get_network_record(self, network):
+        if self.__networks.has_key(network):
+            return self.__networks[network]
+        raise Error("Unknown network \"%s\"" % network)
+
+    def get_bond_record(self, bond):
+        if self.__bonds.has_key(bond):
+            return self.__bonds[bond]
+        else:
+            return None
+
+    def get_vlan_record(self, vlan):
+        if self.__vlans.has_key(vlan):
+            return self.__vlans[vlan]
+        else:
+            return None
+
+#
+#
+#
+
+def ethtool_settings(oc):
+    settings = []
+    if oc.has_key('ethtool-speed'):
+        val = oc['ethtool-speed']
+        if val in ["10", "100", "1000"]:
+            settings += ['speed', val]
+        else:
+            log("Invalid value for ethtool-speed = %s. Must be 10|100|1000." % val)
+    if oc.has_key('ethtool-duplex'):
+        val = oc['ethtool-duplex']
+        if val in ["10", "100", "1000"]:
+            settings += ['duplex', 'val']
+        else:
+            log("Invalid value for ethtool-duplex = %s. Must be half|full." % val)
+    if oc.has_key('ethtool-autoneg'):
+        val = oc['ethtool-autoneg']
+        if val in ["true", "on"]:
+            settings += ['autoneg', 'on']
+        elif val in ["false", "off"]:
+            settings += ['autoneg', 'off']
+        else:
+            log("Invalid value for ethtool-autoneg = %s. Must be on|true|off|false." % val)
+    offload = []
+    for opt in ("rx", "tx", "sg", "tso", "ufo", "gso"):
+        if oc.has_key("ethtool-" + opt):
+            val = oc["ethtool-" + opt]
+            if val in ["true", "on"]:
+                offload += [opt, 'on']
+            elif val in ["false", "off"]:
+                offload += [opt, 'off']
+            else:
+                log("Invalid value for ethtool-%s = %s. Must be on|true|off|false." % (opt, val))
+    return settings,offload
+
+# By default the MTU is taken from the Network.MTU setting for VIF,
+# PIF and Bridge. However it is possible to override this by using
+# {VIF,PIF,Network}.other-config:mtu.
+#
+# type parameter is a string describing the object that the oc parameter
+# is from. e.g. "PIF", "Network" 
+def mtu_setting(nw, type, oc):
+    mtu = None
+
+    nwrec = db().get_network_record(nw)
+    if nwrec.has_key('MTU'):
+        mtu = nwrec['MTU']
+    else:
+        mtu = "1500"
+        
+    if oc.has_key('mtu'):
+        log("Override Network.MTU setting on bridge %s from %s.MTU is %s" % \
+            (nwrec['bridge'], type, mtu))
+        mtu = oc['mtu']
+
+    if mtu is not None:
+        try:
+            int(mtu)      # Check that the value is an integer
+            return mtu
+        except ValueError, x:
+            log("Invalid value for mtu = %s" % mtu)
+
+    return None
+
+#
+# IP Network Devices -- network devices with IP configuration
+#
+def pif_ipdev_name(pif):
+    """Return the ipdev name associated with pif"""
+    pifrec = db().get_pif_record(pif)
+    nwrec = db().get_network_record(pifrec['network'])
+
+    if nwrec['bridge']:
+        # TODO: sanity check that nwrec['bridgeless'] != 'true'
+        return nwrec['bridge']
+    else:
+        # TODO: sanity check that nwrec['bridgeless'] == 'true'
+        return pif_netdev_name(pif)
+
+#
+# Bare Network Devices -- network devices without IP configuration
+#
+
+def netdev_exists(netdev):
+    return os.path.exists(root_prefix() + "/sys/class/net/" + netdev)
+
+def pif_netdev_name(pif):
+    """Get the netdev name for a PIF."""
+
+    pifrec = db().get_pif_record(pif)
+
+    if pif_is_vlan(pif):
+        return "%(device)s.%(VLAN)s" % pifrec
+    else:
+        return pifrec['device']
+
+#
+# Bridges
+#
+
+def pif_is_bridged(pif):
+    pifrec = db().get_pif_record(pif)
+    nwrec = db().get_network_record(pifrec['network'])
+
+    if nwrec['bridge']:
+        # TODO: sanity check that nwrec['bridgeless'] != 'true'
+        return True
+    else:
+        # TODO: sanity check that nwrec['bridgeless'] == 'true'
+        return False
+
+def pif_bridge_name(pif):
+    """Return the bridge name of a pif.
+
+    PIF must be a bridged PIF."""
+    pifrec = db().get_pif_record(pif)
+
+    nwrec = db().get_network_record(pifrec['network'])
+
+    if nwrec['bridge']:
+        return nwrec['bridge']
+    else:
+        raise Error("PIF %(uuid)s does not have a bridge name" % pifrec)
+
+#
+# Bonded PIFs
+#
+def pif_is_bond(pif):
+    pifrec = db().get_pif_record(pif)
+
+    return len(pifrec['bond_master_of']) > 0
+
+def pif_get_bond_masters(pif):
+    """Returns a list of PIFs which are bond masters of this PIF"""
+
+    pifrec = db().get_pif_record(pif)
+
+    bso = pifrec['bond_slave_of']
+
+    # bond-slave-of is currently a single reference but in principle a
+    # PIF could be a member of several bonds which are not
+    # concurrently attached. Be robust to this possibility.
+    if not bso or bso == "OpaqueRef:NULL":
+        bso = []
+    elif not type(bso) == list:
+        bso = [bso]
+
+    bondrecs = [db().get_bond_record(bond) for bond in bso]
+    bondrecs = [rec for rec in bondrecs if rec]
+
+    return [bond['master'] for bond in bondrecs]
+
+def pif_get_bond_slaves(pif):
+    """Returns a list of PIFs which make up the given bonded pif."""
+
+    pifrec = db().get_pif_record(pif)
+
+    bmo = pifrec['bond_master_of']
+    if len(bmo) > 1:
+        raise Error("Bond-master-of contains too many elements")
+
+    if len(bmo) == 0:
+        return []
+
+    bondrec = db().get_bond_record(bmo[0])
+    if not bondrec:
+        raise Error("No bond record for bond master PIF")
+
+    return bondrec['slaves']
+
+#
+# VLAN PIFs
+#
+
+def pif_is_vlan(pif):
+    return db().get_pif_record(pif)['VLAN'] != '-1'
+
+def pif_get_vlan_slave(pif):
+    """Find the PIF which is the VLAN slave of pif.
+
+Returns the 'physical' PIF underneath the a VLAN PIF @pif."""
+
+    pifrec = db().get_pif_record(pif)
+
+    vlan = pifrec['VLAN_master_of']
+    if not vlan or vlan == "OpaqueRef:NULL":
+        raise Error("PIF is not a VLAN master")
+
+    vlanrec = db().get_vlan_record(vlan)
+    if not vlanrec:
+        raise Error("No VLAN record found for PIF")
+
+    return vlanrec['tagged_PIF']
+
+def pif_get_vlan_masters(pif):
+    """Returns a list of PIFs which are VLANs on top of the given pif."""
+
+    pifrec = db().get_pif_record(pif)
+    vlans = [db().get_vlan_record(v) for v in pifrec['VLAN_slave_of']]
+    return [v['untagged_PIF'] for v in vlans if v and db().pif_exists(v['untagged_PIF'])]
+
+#
+# Datapath base class
+#
+
+class Datapath(object):
+    """Object encapsulating the actions necessary to (de)configure the
+       datapath for a given PIF. Does not include configuration of the
+       IP address on the ipdev.
+    """
+    
+    def __init__(self, pif):
+        self._pif = pif
+
+    def configure_ipdev(self, cfg):
+        """Write ifcfg TYPE field for an IPdev, plus any type specific
+           fields to cfg
+        """
+        raise NotImplementedError        
+
+    def preconfigure(self, parent):
+        """Prepare datapath configuration for PIF, but do not actually
+           apply any changes.
+
+           Any configuration files should be attached to parent.
+        """
+        raise NotImplementedError
+    
+    def bring_down_existing(self):
+        """Tear down any existing network device configuration which
+           needs to be undone in order to bring this PIF up.
+        """
+        raise NotImplementedError
+
+    def configure(self):
+        """Apply the configuration prepared in the preconfigure stage.
+
+           Should assume any configuration files changed attached in
+           the preconfigure stage are applied and bring up the
+           necesary devices to provide the datapath for the
+           PIF.
+
+           Should not bring up the IPdev.
+        """
+        raise NotImplementedError
+    
+    def post(self):
+        """Called after the IPdev has been brought up.
+
+           Should do any final setup, including reinstating any
+           devices which were taken down in the bring_down_existing
+           hook.
+        """
+        raise NotImplementedError
+
+    def bring_down(self):
+        """Tear down and deconfigure the datapath. Should assume the
+           IPdev has already been brought down.
+        """
+        raise NotImplementedError
+        
+def DatapathFactory(pif):
+    # XXX Need a datapath object for bridgeless PIFs
+
+    try:
+        network_conf = open(root_prefix() + "/etc/xensource/network.conf", 'r')
+        network_backend = network_conf.readline().strip()
+        network_conf.close()                
+    except Exception, e:
+        raise Error("failed to determine network backend:" + e)
+    
+    if network_backend == "bridge":
+        from InterfaceReconfigureBridge import DatapathBridge
+        return DatapathBridge(pif)
+    elif network_backend in ["openvswitch", "vswitch"]:
+        from InterfaceReconfigureVswitch import DatapathVswitch
+        return DatapathVswitch(pif)
+    else:
+        raise Error("unknown network backend %s" % network_backend)
diff --git a/scripts/vm/hypervisor/xenserver/xenserver56/patch b/scripts/vm/hypervisor/xenserver/xenserver56/patch
index 944962b6b37..dba8a9b8a36 100644
--- a/scripts/vm/hypervisor/xenserver/xenserver56/patch
+++ b/scripts/vm/hypervisor/xenserver/xenserver56/patch
@@ -31,3 +31,14 @@ networkUsage.sh=../../../../network/domr/,0755,/opt/xensource/bin
 call_firewall.sh=../../../../network/domr/,0755,/opt/xensource/bin
 call_loadbalancer.sh=../../../../network/domr/,0755,/opt/xensource/bin
 l2tp_vpn.sh=../../../../network/domr/,0755,/opt/xensource/bin
+copy_vhd_to_secondarystorage.sh=..,0755,/opt/xensource/bin
+copy_vhd_from_secondarystorage.sh=..,0755,/opt/xensource/bin
+setup_heartbeat_sr.sh=..,0755,/opt/xensource/bin
+setup_heartbeat_file.sh=..,0755,/opt/xensource/bin
+check_heartbeat.sh=..,0755,/opt/xensource/bin
+xenheartbeat.sh=..,0755,/opt/xensource/bin
+launch_hb.sh=..,0755,/opt/xensource/bin
+setupXenServer.sh=..,0755,/opt/xensource/bin
+vmopspremium=..,0755,/etc/xapi.d/plugins
+InterfaceReconfigure.py=.,0755,/opt/xensource/bin
+fsimage.so=..,0755,/usr/lib/fs/ext2fs-lib
diff --git a/scripts/vm/hypervisor/xenserver/xenserver56fp1/patch b/scripts/vm/hypervisor/xenserver/xenserver56fp1/patch
index 9f7c0d0d193..bc1d2c8ed12 100644
--- a/scripts/vm/hypervisor/xenserver/xenserver56fp1/patch
+++ b/scripts/vm/hypervisor/xenserver/xenserver56fp1/patch
@@ -33,3 +33,12 @@ call_firewall.sh=../../../../network/domr/,0755,/opt/xensource/bin
 call_loadbalancer.sh=../../../../network/domr/,0755,/opt/xensource/bin
 l2tp_vpn.sh=../../../../network/domr/,0755,/opt/xensource/bin
 cloud-setup-bonding.sh=..,0755,/opt/xensource/bin
+copy_vhd_to_secondarystorage.sh=..,0755,/opt/xensource/bin
+copy_vhd_from_secondarystorage.sh=..,0755,/opt/xensource/bin
+setup_heartbeat_sr.sh=..,0755,/opt/xensource/bin
+setup_heartbeat_file.sh=..,0755,/opt/xensource/bin
+check_heartbeat.sh=..,0755,/opt/xensource/bin
+xenheartbeat.sh=..,0755,/opt/xensource/bin
+launch_hb.sh=..,0755,/opt/xensource/bin
+setupXenServer.sh=..,0755,/opt/xensource/bin
+vmopspremium=..,0755,/etc/xapi.d/plugins
diff --git a/scripts/vm/hypervisor/xenserver/xs_cleanup.sh b/scripts/vm/hypervisor/xenserver/xs_cleanup.sh
new file mode 100755
index 00000000000..cb81a3f16ef
--- /dev/null
+++ b/scripts/vm/hypervisor/xenserver/xs_cleanup.sh
@@ -0,0 +1,54 @@
+#!/bin/bash
+
+#set -x
+ 
+usage() {
+  printf "Usage: %s \n" $(basename $0) >&2
+
+}
+
+# remove device which is in xenstore but not in xapi
+remove_device() {
+  be=$1
+  xenstore-write /local/domain/0/backend/tap/0/$be/online 0 &>/dev/null
+  xenstore-write /local/domain/0/backend/tap/0/$be/shutdown-request normal &>/dev/null
+  for i in $(seq 20)
+  do
+    sleep 1
+    xenstore-exists /local/domain/0/backend/tap/0/$be/shutdown-done &>/dev/null
+    if [ $? -eq 0 ] ; then
+      xenstore-rm /local/domain/0/device/vbd/$be &>/dev/null
+      xenstore-rm /local/domain/0/backend/tap/0/$be &>/dev/null
+      xenstore-rm /local/domain/0/error/backend/tap/0/$be &>/dev/null
+      xenstore-rm /local/domain/0/error/device/vbd/$be &>/dev/null
+      return
+    fi
+    xenstore-exists /local/domain/0/backend/tap/0/$be &>/dev/null
+    if [ $? -ne 0 ] ; then
+      return
+    fi
+  done
+
+  echo "unplug device $be failed"
+  exit 2
+}
+
+bes=`xenstore-list /local/domain/0/backend/tap/0`
+
+if [ -z "$bes" ]; then
+  exit 0
+fi
+
+for be in $bes
+do
+  device=`xenstore-read /local/domain/0/backend/tap/0/$be/dev`
+  ls $device >/dev/null 2>&1 
+  if [ $? -ne 0 ]; then
+    remove_device $be
+  fi
+done
+
+
+echo "======> DONE <======"
+exit 0
+