diff --git a/Makefile b/Makefile
new file mode 100644
index 00000000..d830bb97
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,97 @@
+# destinations
+DESTDIR =
+INSTALLER_DIR = /opt/xensource/installer
+EFI_DIR = /EFI/xenserver
+
+# root of a tree with sm.rpm unpacked
+SM_ROOTDIR =
+
+INSTALL = install
+
+install:
+	$(INSTALL) -d $(DESTDIR)/usr/bin
+	$(INSTALL) -m755 support.sh $(DESTDIR)/usr/bin
+	$(INSTALL) -d $(DESTDIR)$(INSTALLER_DIR)/tui/installer/
+	$(INSTALL) -m755 \
+	        init \
+	    $(DESTDIR)$(INSTALLER_DIR)/
+	$(INSTALL) -m644 \
+	        keymaps \
+	        timezones \
+	        answerfile.py \
+	        backend.py \
+	        common_criteria_firewall_rules \
+	        constants.py \
+	        cpiofile.py \
+	        disktools.py \
+	        diskutil.py \
+	        driver.py \
+	        fcoeutil.py \
+	        generalui.py \
+	        hardware.py \
+	        init_constants.py \
+	        install.py \
+	        netinterface.py \
+	        netutil.py \
+	        product.py \
+	        report.py \
+	        repository.py \
+	        restore.py \
+	        scripts.py \
+	        snackutil.py \
+	        uicontroller.py \
+	        upgrade.py \
+	        util.py \
+	        xelogging.py \
+	    $(DESTDIR)$(INSTALLER_DIR)/
+	$(INSTALL) -m644 \
+	        tui/__init__.py \
+	        tui/init.py \
+	        tui/fcoe.py \
+	        tui/network.py \
+	        tui/progress.py \
+	        tui/repo.py \
+	    $(DESTDIR)$(INSTALLER_DIR)/tui/
+	$(INSTALL) -m644 \
+	        tui/installer/__init__.py \
+	        tui/installer/screens.py \
+	    $(DESTDIR)$(INSTALLER_DIR)/tui/installer/
+
+ # Startup files
+	$(INSTALL) -d \
+	    $(DESTDIR)/etc/init.d \
+	    $(DESTDIR)/etc/modprobe.d \
+	    $(DESTDIR)/etc/modules-load.d \
+	    $(DESTDIR)/etc/depmod.d \
+	    $(DESTDIR)/etc/dracut.conf.d \
+	    $(DESTDIR)/etc/udev/rules.d \
+	    $(DESTDIR)/etc/systemd/system/systemd-udevd.d
+
+	$(INSTALL) -m755 startup/interface-rename-sideway startup/early-blacklist $(DESTDIR)/etc/init.d/
+	$(INSTALL) -m644 startup/functions $(DESTDIR)/etc/init.d/installer-functions
+	$(INSTALL) -m644 startup/early-blacklist.conf startup/bnx2x.conf $(DESTDIR)/etc/modprobe.d/
+	$(INSTALL) -m644 startup/blacklist $(DESTDIR)/etc/modprobe.d/installer-blacklist.conf
+	$(INSTALL) -m644 startup/modprobe.mlx4 $(DESTDIR)/etc/modprobe.d/mlx4.conf
+	$(INSTALL) -m644 startup/iscsi-modules $(DESTDIR)/etc/modules-load.d/iscsi.conf
+	$(INSTALL) -m644 startup/depmod.conf $(DESTDIR)/etc/depmod.d/
+	$(INSTALL) -m755 startup/preinit startup/S05ramdisk startup/S06mount $(DESTDIR)/$(INSTALLER_DIR)/
+	$(INSTALL) -m644 startup/01-installer.rules $(DESTDIR)/etc/udev/rules.d/
+	$(INSTALL) -m644 startup/systemd-udevd_depmod.conf $(DESTDIR)/etc/systemd/system/systemd-udevd.d/installer.conf
+
+ # Generate a multipath configuration from sm's copy, removing
+ # the blacklist and blacklist_exception sections.
+	sed 's/\(^[[:space:]]*find_multipaths[[:space:]]*\)yes/\1no/' \
+	    < $(SM_ROOTDIR)/etc/multipath.xenserver/multipath.conf \
+	    > $(DESTDIR)/etc/multipath.conf.disabled
+
+ # bootloader files
+	$(INSTALL) -D -m644 bootloader/grub.cfg $(DESTDIR)$(EFI_DIR)/grub.cfg
+	$(INSTALL) -D -m644 bootloader/grub.cfg $(DESTDIR)$(EFI_DIR)/grub-usb.cfg
+
+	sed -i '/^set timeout=[0-9]\+$/asearch --file --set /install.img' \
+	    $(DESTDIR)$(EFI_DIR)/grub-usb.cfg
+
+	$(INSTALL) -D -m644 bootloader/isolinux.cfg $(DESTDIR)/boot/isolinux/isolinux.cfg
+
+	printf "echo Skipping initrd creation in the installer\nexit 0\n" \
+	    > $(DESTDIR)/etc/dracut.conf.d/installer.conf
diff --git a/answerfile.py b/answerfile.py
index 490b49ec..2dd5360e 100644
--- a/answerfile.py
+++ b/answerfile.py
@@ -133,6 +133,7 @@ def parseFreshInstall(self):
         results['preserve-settings'] = False
         results['backup-existing-installation'] = False
 
+        results.update(self.parseAssembleRaid())
         results.update(self.parseDisks())
         results.update(self.parseInterface())
         results.update(self.parseRootPassword())
@@ -170,6 +171,7 @@ def parseRestore(self):
 
         results['install-type'] = INSTALL_TYPE_RESTORE
 
+        results.update(self.parseAssembleRaid())
         backups = product.findXenSourceBackups()
         if len(backups) == 0:
             raise AnswerfileException("Could not locate exsisting backup.")
@@ -227,6 +229,7 @@ def parseCommon(self):
     def parseExistingInstallation(self):
         results = {}
 
+        results.update(self.parseAssembleRaid())
         inst = getElementsByTagName(self.top_node, ['existing-installation'],
                                     mandatory=True)
         disk = normalize_disk(getText(inst[0]))
@@ -293,6 +296,15 @@ def parseDriverSource(self):
             results['extra-repos'].append((rtype, address))
         return results
 
+    def parseAssembleRaid(self):
+        results = {}
+        nodes = getElementsByTagName(self.top_node, ['assemble-raid'])
+        if nodes:
+            results['assemble-raid'] = True # possibly useless
+            logger.log("Assembling any RAID volumes")
+            rv = util.runCmd2([ 'mdadm', '--assemble', "--scan" ])
+        return results
+
     def parseDisks(self):
         results = {}
 
diff --git a/constants.py b/constants.py
index 7b414802..1dc3d4eb 100644
--- a/constants.py
+++ b/constants.py
@@ -181,3 +181,7 @@ def error_string(error, logname, with_hd):
     'var/lib/misc/ran-network-init',
     'var/lib/misc/ran-storage-init',
 ]
+
+# optional features
+FEATURES_DIR = "/etc/xensource/features"
+HAS_RAID_ASSEMBLE = os.path.exists(os.path.join(FEATURES_DIR, "raid-assemble"))
diff --git a/diskutil.py b/diskutil.py
index 952977b4..cac8d2a0 100644
--- a/diskutil.py
+++ b/diskutil.py
@@ -365,9 +365,9 @@ def getMdDeviceName(disk):
     rv, out = util.runCmd2(['mdadm', '--detail', '--export', disk],
                            with_stdout=True)
     for line in out.split("\n"):
-        line = line.strip().split('=', 1)
-        if line[0] == 'MD_DEVNAME':
-            return line[1]
+        key, value = line.strip().split('=', 1)
+        if key == 'MD_DEVNAME':
+            return "md%s" % value
 
     return disk
 
@@ -392,6 +392,12 @@ def getHumanDiskName(disk):
         return disk[5:]
     return disk
 
+def getHumanDiskLabel(disk, short=False):
+    (vendor, model, size) = getExtendedDiskInfo(disk)
+    template = "{device} - {size} [{vendor} {model}]" if not short else "{device} - {size}"
+    return template.format(device=getHumanDiskName(disk), size=getHumanDiskSize(size),
+                           vendor=vendor, model=model)
+
 # given a list of disks, work out which ones are part of volume
 # groups that will cause a problem if we install XE to those disks:
 def findProblematicVGs(disks):
diff --git a/doc/answerfile.txt b/doc/answerfile.txt
index 76221624..a4093b62 100644
--- a/doc/answerfile.txt
+++ b/doc/answerfile.txt
@@ -129,6 +129,15 @@ Common Elements
     Discovery on.
 
 
+  <assemble-raid/>?
+
+    Run `mdadm --assemble --scan` before looking for the device
+    specified in <primary-disk>, <existing-installation>, or
+    <backup-disk>.
+
+    Used to be the default behavior.
+
+
 (Re)Install Elements
 --------------------
 
diff --git a/doc/features.txt b/doc/features.txt
new file mode 100644
index 00000000..20fabd43
--- /dev/null
+++ b/doc/features.txt
@@ -0,0 +1,18 @@
+Features flags
+==============
+
+Some host-installer features are not enabled by default, and
+downstream installers can activate them by creating a file in
+/etc/xensource/features/ in their installer filesystem.
+
+Currently available feature flags are:
+
+  raid-assemble
+
+    Detect Linux software-RAID (a.k.a "md") superblocks in disks, adds
+    a choice for the user to activate software RAID volumes, and do
+    not offer the user the ability to upgrade or restore a system on a
+    software-RAID device.
+
+    This only impacts the UI, the <assemble-raid/> answerfile
+    construct does not need this feature flag.
diff --git a/startup/01-installer.rules b/startup/01-installer.rules
new file mode 100644
index 00000000..5267d3ef
--- /dev/null
+++ b/startup/01-installer.rules
@@ -0,0 +1,2 @@
+# disable 65-md-incremental.rules by telling an installer is running
+ENV{ANACONDA}="1"
diff --git a/tui/installer/__init__.py b/tui/installer/__init__.py
index 7a8f588f..9e3f46d9 100644
--- a/tui/installer/__init__.py
+++ b/tui/installer/__init__.py
@@ -124,10 +124,10 @@ def out_of_order_pool_upgrade_fn(answers):
         Step(uis.hardware_warnings,
              args=[ram_warning, vt_warning],
              predicates=[lambda _:(ram_warning or vt_warning)]),
+        Step(uis.scan_existing),
         Step(uis.overwrite_warning,
              predicates=[only_unupgradeable_products]),
-        Step(uis.get_installation_type,
-             predicates=[lambda _:len(results['upgradeable-products']) > 0 or len(results['backups']) > 0]),
+        Step(uis.get_installation_type),
         Step(uis.upgrade_settings_warning,
              predicates=[upgrade_but_no_settings_predicate]),
         Step(uis.ha_master_upgrade,
diff --git a/tui/installer/screens.py b/tui/installer/screens.py
index e7b52721..4051ba42 100644
--- a/tui/installer/screens.py
+++ b/tui/installer/screens.py
@@ -111,14 +111,6 @@ def fn10():
     lvm.deactivateAll()
     del lvm
 
-    tui.progress.showMessageDialog("Please wait", "Checking for existing products...")
-    answers['installed-products'] = product.find_installed_products()
-    answers['upgradeable-products'] = upgrade.filter_for_upgradeable_products(answers['installed-products'])
-    answers['backups'] = product.findXenSourceBackups()
-    tui.progress.clearModelessDialog()
-
-    diskutil.log_available_disks()
-
     # CA-41142, ensure we have at least one network interface and one disk before proceeding
     label = None
     if len(diskutil.getDiskList()) == 0:
@@ -160,6 +152,22 @@ def hardware_warnings(answers, ram_warning, vt_warning):
     if button == 'back': return LEFT_BACKWARDS
     return RIGHT_FORWARDS
 
+def scan_existing(answers):
+    tui.progress.showMessageDialog("Please wait", "Checking for existing products...")
+
+    if 'assemble-raid' in answers:
+        logger.log("Assembling any RAID volumes")
+        rv = util.runCmd2([ 'mdadm', '--assemble', "--scan" ])
+
+    answers['installed-products'] = product.find_installed_products()
+    answers['upgradeable-products'] = upgrade.filter_for_upgradeable_products(answers['installed-products'])
+    answers['backups'] = product.findXenSourceBackups()
+    tui.progress.clearModelessDialog()
+
+    diskutil.log_available_disks()
+
+    return RIGHT_FORWARDS
+
 def overwrite_warning(answers):
     warning_string = "Continuing will result in a clean installation, all existing configuration will be lost."
     warning_string += "\n\nAlternatively, please contact a Technical Support Representative for the recommended upgrade path."
@@ -216,11 +224,44 @@ def get_admin_interface_configuration(answers):
     return rc
 
 def get_installation_type(answers):
-    entries = []
+
+    # If we were not already told to enable RAID, build a full list of
+    # RAID members, for filtering out from upgradable-products and
+    # backups, and to decide whether to propose to activate existing RAID.
+    raid_members = []
+    if constants.HAS_RAID_ASSEMBLE and "assemble-raid" not in answers:
+        for disk in diskutil.getQualifiedDiskList():
+            rv, out = util.runCmd2([ 'mdadm', '--examine', disk ], with_stdout=True)
+            if rv == 0 and re.search("Array UUID :", out):
+                raid_members.append(disk)
+
+    upgradeable_products = []
     for x in answers['upgradeable-products']:
-        entries.append(("Upgrade %s" % str(x), (x, x.settingsAvailable())))
+        if x.primary_disk in raid_members:
+            logger.log("%s: disk %s in %s, skipping" % (x, x.primary_disk, raid_members))
+            continue
+        upgradeable_products.append(x)
+    backups = []
     for b in answers['backups']:
-        entries.append(("Restore %s from backup" % str(b), (b, None)))
+        if not os.path.exists(b.root_disk):
+            logger.log("%s: disk %s not found, skipping" % (b, b.root_disk))
+            continue
+        if b.root_disk in raid_members:
+            logger.log("%s: disk %s in %s, skipping" % (b, b.root_disk, raid_members))
+            continue
+        backups.append(b)
+
+    entries = []
+    for x in upgradeable_products:
+        entries.append(("Upgrade %s on %s" % (x, diskutil.getHumanDiskLabel(x.primary_disk, short=True)),
+                        (x, x.settingsAvailable())))
+    for b in backups:
+        entries.append(("Restore %s from backup to %s" % (b, diskutil.getHumanDiskLabel(b.root_disk, short=True)),
+                        (b, None)))
+
+    if raid_members:
+        logger.log("Found a MD RAID on: %s" % ", ".join(raid_members))
+        entries.append(("Assemble software RAID volumes", ("RAID", None)))
 
     entries.append( ("Perform clean installation", None) )
 
@@ -232,12 +273,21 @@ def get_installation_type(answers):
     else:
         default = None
 
-    if len(answers['upgradeable-products']) > 0:
-        text = "One or more existing product installations that can be upgraded have been detected."
-        if len(answers['backups']) > 0:
-            text += "  In addition one or more backups have been detected."
+    if upgradeable_products or backups:
+        if upgradeable_products:
+            text = "One or more existing product installations that can be upgraded have been detected."
+            if backups:
+                text += "  In addition one or more backups have been detected."
+        else:
+            text = "One or more backups have been detected."
+        if raid_members:
+            text += "  Also, some disks have been identified as members of a sofware-RAID volume."
+    elif raid_members:
+        text = "Some disks have been identified as members of a sofware-RAID volume."
     else:
-        text = "One or more backups have been detected."
+        text = "No existing product installation or backup was detected."
+    if raid_members:
+        text += "  RAID volumes may themselves contain more upgradeable products or backups."
     text += "\n\nWhat would you like to do?"
 
     tui.update_help_line([None, "<F5> more info"])
@@ -306,6 +356,10 @@ def more_info(context):
     elif isinstance(entry[0], product.XenServerBackup):
         answers['install-type'] = constants.INSTALL_TYPE_RESTORE
         answers['backup-to-restore'], _ = entry
+    elif entry[0] == "RAID":
+        # go rescan for products after assembling RAID volumes
+        answers['assemble-raid'] = True
+        return LEFT_BACKWARDS
 
     return RIGHT_FORWARDS
 
@@ -556,9 +610,7 @@ def select_primary_disk(answers):
         (boot, root, state, storage, logs) = diskutil.probeDisk(de)
         if storage[0]:
             target_is_sr[de] = True
-        (vendor, model, size) = diskutil.getExtendedDiskInfo(de)
-        stringEntry = "%s - %s [%s %s]" % (diskutil.getHumanDiskName(de), diskutil.getHumanDiskSize(size), vendor, model)
-        e = (stringEntry, de)
+        e = (diskutil.getHumanDiskLabel(de), de)
         entries.append(e)
 
     # we should have at least one disk
@@ -665,9 +717,7 @@ def select_guest_disks(answers):
     # Make a list of entries: (text, item)
     entries = []
     for de in diskEntries:
-        (vendor, model, size) = diskutil.getExtendedDiskInfo(de)
-        entry = "%s - %s [%s %s]" % (diskutil.getHumanDiskName(de), diskutil.getHumanDiskSize(size), vendor, model)
-        entries.append((entry, de))
+        entries.append((diskutil.getHumanDiskLabel(de), de))
 
     text = TextboxReflowed(54, "Which disks would you like to use for %s storage?  \n\nOne storage repository will be created that spans the selected disks.  You can choose not to prepare any storage if you wish to create an advanced configuration after installation." % BRAND_GUEST)
     buttons = ButtonBar(tui.screen, [('Ok', 'ok'), ('Back', 'back')])