# # Common code for all guests # # Copyright 2006-2009, 2013 Red Hat, Inc. # Jeremy Katz # # This work is licensed under the GNU GPLv2 or later. # See the COPYING file in the top-level directory. import os import logging import libvirt from .devices import DeviceDisk from .domain import DomainOs from . import util class Installer(object): """ Installer classes attempt to encapsulate all the parameters needed to 'install' a guest: essentially, booting the guest with the correct media for the OS install phase (if there is one), and setting up the guest to boot to the correct media for all subsequent runs. Some of the actual functionality: - Determining what type of install media has been requested, and representing it correctly to the Guest - Fetching install kernel/initrd or boot.iso from a URL - Setting the boot device as appropriate depending on whether we are booting into an OS install, or booting post-install Some of the information that the Installer needs to know to accomplish this: - Install media location (could be a URL, local path, ...) - Virtualization type (parameter 'os_type') ('xen', 'hvm', etc.) - Hypervisor name (parameter 'type') ('qemu', 'kvm', 'xen', etc.) - Guest architecture ('i686', 'x86_64') """ def __init__(self, conn): self.conn = conn self._location = None self.cdrom = False self.livecd = False self.extraargs = [] self.install_bootdev = None self.initrd_injections = [] self._install_kernel = None self._install_initrd = None self._install_cdrom_device = None self._defaults_are_set = False self._tmpfiles = [] self._tmpvols = [] ######################### # Properties properties # ######################### def get_location(self): return self._location def set_location(self, val): self._location = self._validate_location(val) location = property(get_location, set_location) ################### # Private helpers # ################### def _add_install_cdrom_device(self, guest): if self._install_cdrom_device: return if not self.needs_cdrom(): return dev = DeviceDisk(self.conn) dev.device = dev.DEVICE_CDROM self._install_cdrom_device = dev guest.add_device(dev) def _insert_install_cdrom_media(self, guest): ignore = guest if not self._install_cdrom_device: return self._install_cdrom_device.path = self.cdrom_path() self._install_cdrom_device.sync_path_props() self._install_cdrom_device.validate() def _remove_install_cdrom_media(self, guest): if not self._install_cdrom_device: return if self.livecd: return if guest.osinfo.is_windows(): # Keep media attached for windows which has a multi stage install return self._install_cdrom_device.path = None self._install_cdrom_device.sync_path_props() def _build_boot_order(self, guest, bootdev): bootorder = [bootdev] # If guest has an attached disk, always have 'hd' in the boot # list, so disks are marked as bootable/installable (needed for # windows virtio installs, and booting local disk from PXE) for disk in guest.devices.disk: if disk.device == disk.DEVICE_DISK: bootdev = "hd" if bootdev not in bootorder: bootorder.append(bootdev) break return bootorder def _can_set_guest_bootorder(self, guest): return (not guest.os.is_container() and not guest.os.kernel and not any([d.boot.order for d in guest.devices.get_all()])) def _alter_bootconfig(self, guest): """ Generate the portion of the guest xml that determines boot devices and parameters. (typically the block) :param guest: Guest instance we are installing """ guest.on_reboot = "destroy" if self._install_kernel: guest.os.kernel = self._install_kernel if self._install_initrd: guest.os.initrd = self._install_initrd if self.extraargs: guest.os.kernel_args = " ".join(self.extraargs) bootdev = self.install_bootdev if bootdev and self._can_set_guest_bootorder(guest): guest.os.bootorder = self._build_boot_order(guest, bootdev) else: guest.os.bootorder = [] ########################## # Internal API overrides # ########################## def _validate_location(self, val): return val def _prepare(self, guest, meter): ignore = guest ignore = meter def _cleanup(self, guest): ignore = guest for f in self._tmpfiles: logging.debug("Removing %s", str(f)) os.unlink(f) for vol in self._tmpvols: logging.debug("Removing volume '%s'", vol.name()) vol.delete(0) self._tmpvols = [] self._tmpfiles = [] def _get_postinstall_bootdev(self, guest): if self.install_bootdev: if any([d for d in guest.devices.disk if d.device == d.DEVICE_DISK]): return DomainOs.BOOT_DEVICE_HARDDISK return DomainOs.BOOT_DEVICE_NETWORK device = guest.devices.disk and guest.devices.disk[0].device or None if device == DeviceDisk.DEVICE_DISK: return DomainOs.BOOT_DEVICE_HARDDISK elif device == DeviceDisk.DEVICE_CDROM: return DomainOs.BOOT_DEVICE_CDROM elif device == DeviceDisk.DEVICE_FLOPPY: return DomainOs.BOOT_DEVICE_FLOPPY return DomainOs.BOOT_DEVICE_HARDDISK ############## # Public API # ############## def set_install_defaults(self, guest): """ Allow API users to set defaults ahead of time if they want it. Used by vmmDomainVirtinst so the 'Customize before install' dialog shows accurate values. If the user doesn't explicitly call this, it will be called by start_install() """ if self._defaults_are_set: return self._add_install_cdrom_device(guest) if not guest.os.bootorder and self._can_set_guest_bootorder(guest): bootdev = self._get_postinstall_bootdev(guest) guest.os.bootorder = self._build_boot_order(guest, bootdev) guest.set_defaults(None) self._defaults_are_set = True def scratchdir_required(self): """ Returns true if scratchdir is needed for the passed install parameters. Apps can use this to determine if they should attempt to ensure scratchdir permissions are adequate """ return False def has_install_phase(self): """ Return True if the requested setup is actually installing an OS into the guest. Things like LiveCDs, Import, or a manually specified bootorder do not have an install phase. """ return bool(self.install_bootdev) def needs_cdrom(self): """ If this installer uses cdrom media, so it needs a cdrom device attached to the VM """ return False def cdrom_path(self): """ Return the cdrom path needed for needs_cdrom() installs """ return None def check_location(self, guest): """ Validate self.location seems to work. This will might hit the network so we don't want to do it on demand. """ ignore = guest return True def detect_distro(self, guest): """ Attempt to detect the distro for the Installer's 'location'. If an error is encountered in the detection process (or if detection is not relevant for the Installer type), None is returned. :returns: distro variant string, or None """ ignore = guest logging.debug("distro detection not available for this installer.") return None ########################## # guest install handling # ########################## def _prepare_get_install_xml(self, guest): # We do a shallow copy of the OS block here, so that we can # set the install time properties but not permanently overwrite # any config the user explicitly requested. data = (guest.os.bootorder, guest.os.kernel, guest.os.initrd, guest.os.kernel_args, guest.on_reboot) return data def _finish_get_install_xml(self, guest, data): (guest.os.bootorder, guest.os.kernel, guest.os.initrd, guest.os.kernel_args, guest.on_reboot) = data def _get_install_xml(self, guest): data = self._prepare_get_install_xml(guest) try: self._alter_bootconfig(guest) self._insert_install_cdrom_media(guest) ret = guest.get_xml() return ret finally: self._remove_install_cdrom_media(guest) self._finish_get_install_xml(guest, data) def _build_xml(self, guest): install_xml = None if self.has_install_phase(): install_xml = self._get_install_xml(guest) else: self._insert_install_cdrom_media(guest) final_xml = guest.get_xml() logging.debug("Generated install XML: %s", (install_xml and ("\n" + install_xml) or "None required")) logging.debug("Generated boot XML: \n%s", final_xml) return install_xml, final_xml def _manual_transient_create(self, install_xml, final_xml, needs_boot): """ For hypervisors (like vz) that don't implement createXML, we need to define+start, and undefine on start failure """ domain = self.conn.defineXML(install_xml or final_xml) if not needs_boot: return domain # Handle undefining the VM if the initial startup fails try: domain.create() except Exception: try: domain.undefine() except Exception: pass raise if install_xml and install_xml != final_xml: domain = self.conn.defineXML(final_xml) return domain def _create_guest(self, guest, meter, install_xml, final_xml, doboot, transient): """ Actually do the XML logging, guest defining/creating :param doboot: Boot guest even if it has no install phase """ meter_label = _("Creating domain...") meter = util.ensure_meter(meter) meter.start(size=None, text=meter_label) needs_boot = doboot or self.has_install_phase() if guest.type == "vz": if transient: raise RuntimeError(_("Domain type 'vz' doesn't support " "transient installs.")) domain = self._manual_transient_create( install_xml, final_xml, needs_boot) else: if transient or needs_boot: domain = self.conn.createXML(install_xml or final_xml, 0) if not transient: domain = self.conn.defineXML(final_xml) try: logging.debug("XML fetched from libvirt object:\n%s", domain.XMLDesc(0)) except Exception as e: logging.debug("Error fetching XML from libvirt object: %s", e) return domain def _flag_autostart(self, domain): """ Set the autostart flag for domain if the user requested it """ try: domain.setAutostart(True) except libvirt.libvirtError as e: if util.is_error_nosupport(e): logging.warning("Could not set autostart flag: libvirt " "connection does not support autostart.") else: raise e ###################### # Public install API # ###################### def start_install(self, guest, meter=None, dry=False, return_xml=False, doboot=True, transient=False, autostart=False): """ Begin the guest install. Will add install media to the guest config, launch it, then redefine the XML with the postinstall config. :param return_xml: Don't create the guest, just return generated XML :param autostart: If True, mark the VM to autostart on host boot """ guest.validate_name(guest.conn, guest.name) self.set_install_defaults(guest) try: self._cleanup(guest) self._prepare(guest, meter) if not dry: for dev in guest.devices.disk: dev.build_storage(meter) install_xml, final_xml = self._build_xml(guest) if return_xml: return (install_xml, final_xml) if dry: return domain = self._create_guest( guest, meter, install_xml, final_xml, doboot, transient) if autostart: self._flag_autostart(domain) return domain finally: self._cleanup(guest) def get_created_disks(self, guest): return [d for d in guest.devices.disk if d.storage_was_created] def cleanup_created_disks(self, guest, meter): """ Remove any disks we created as part of the install. Only ever called by clients. """ clean_disks = self.get_created_disks(guest) if not clean_disks: return for disk in clean_disks: logging.debug("Removing created disk path=%s vol_object=%s", disk.path, disk.get_vol_object()) name = os.path.basename(disk.path) try: meter.start(size=None, text=_("Removing disk '%s'") % name) if disk.get_vol_object(): disk.get_vol_object().delete() else: os.unlink(disk.path) meter.end(0) except Exception as e: logging.debug("Failed to remove disk '%s'", name, exc_info=True) logging.error("Failed to remove disk '%s': %s", name, e)