4 # Copyright (C) 2006, 2007 Google Inc.
6 # This program is free software; you can redistribute it and/or modify
7 # it under the terms of the GNU General Public License as published by
8 # the Free Software Foundation; either version 2 of the License, or
9 # (at your option) any later version.
11 # This program is distributed in the hope that it will be useful, but
12 # WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 # General Public License for more details.
16 # You should have received a copy of the GNU General Public License
17 # along with this program; if not, write to the Free Software
18 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
22 """Block device abstraction"""
27 import pyparsing as pyp
31 from ganeti import utils
32 from ganeti import errors
33 from ganeti import constants
36 def _IgnoreError(fn, *args, **kwargs):
37 """Executes the given function, ignoring BlockDeviceErrors.
39 This is used in order to simplify the execution of cleanup or
43 @return: True when fn didn't raise an exception, False otherwise
49 except errors.BlockDeviceError, err:
50 logging.warning("Caught BlockDeviceError but ignoring: %s" % str(err))
54 def _ThrowError(msg, *args):
55 """Log an error to the node daemon and the raise an exception.
58 @param msg: the text of the exception
59 @raise errors.BlockDeviceError
65 raise errors.BlockDeviceError(msg)
68 class BlockDev(object):
69 """Block device abstract class.
71 A block device can be in the following states:
72 - not existing on the system, and by `Create()` it goes into:
73 - existing but not setup/not active, and by `Assemble()` goes into:
74 - active read-write and by `Open()` it goes into
75 - online (=used, or ready for use)
77 A device can also be online but read-only, however we are not using
78 the readonly state (LV has it, if needed in the future) and we are
79 usually looking at this like at a stack, so it's easier to
80 conceptualise the transition from not-existing to online and back
83 The many different states of the device are due to the fact that we
84 need to cover many device types:
85 - logical volumes are created, lvchange -a y $lv, and used
86 - drbd devices are attached to a local disk/remote peer and made primary
88 A block device is identified by three items:
89 - the /dev path of the device (dynamic)
90 - a unique ID of the device (static)
91 - it's major/minor pair (dynamic)
93 Not all devices implement both the first two as distinct items. LVM
94 logical volumes have their unique ID (the pair volume group, logical
95 volume name) in a 1-to-1 relation to the dev path. For DRBD devices,
96 the /dev path is again dynamic and the unique id is the pair (host1,
99 You can get to a device in two ways:
100 - creating the (real) device, which returns you
101 an attached instance (lvcreate)
102 - attaching of a python instance to an existing (real) device
104 The second point, the attachement to a device, is different
105 depending on whether the device is assembled or not. At init() time,
106 we search for a device with the same unique_id as us. If found,
107 good. It also means that the device is already assembled. If not,
108 after assembly we'll have our correct major/minor.
111 def __init__(self, unique_id, children):
112 self._children = children
114 self.unique_id = unique_id
117 self.attached = False
120 """Assemble the device from its components.
122 Implementations of this method by child classes must ensure that:
123 - after the device has been assembled, it knows its major/minor
124 numbers; this allows other devices (usually parents) to probe
125 correctly for their children
126 - calling this method on an existing, in-use device is safe
127 - if the device is already configured (and in an OK state),
128 this method is idempotent
134 """Find a device which matches our config and attach to it.
137 raise NotImplementedError
140 """Notifies that the device will no longer be used for I/O.
143 raise NotImplementedError
146 def Create(cls, unique_id, children, size):
147 """Create the device.
149 If the device cannot be created, it will return None
150 instead. Error messages go to the logging system.
152 Note that for some devices, the unique_id is used, and for other,
153 the children. The idea is that these two, taken together, are
154 enough for both creation and assembly (later).
157 raise NotImplementedError
160 """Remove this device.
162 This makes sense only for some of the device types: LV and file
163 storeage. Also note that if the device can't attach, the removal
167 raise NotImplementedError
169 def Rename(self, new_id):
170 """Rename this device.
172 This may or may not make sense for a given device type.
175 raise NotImplementedError
177 def Open(self, force=False):
178 """Make the device ready for use.
180 This makes the device ready for I/O. For now, just the DRBD
183 The force parameter signifies that if the device has any kind of
184 --force thing, it should be used, we know what we are doing.
187 raise NotImplementedError
190 """Shut down the device, freeing its children.
192 This undoes the `Assemble()` work, except for the child
193 assembling; as such, the children on the device are still
194 assembled after this call.
197 raise NotImplementedError
199 def SetSyncSpeed(self, speed):
200 """Adjust the sync speed of the mirror.
202 In case this is not a mirroring device, this is no-op.
207 for child in self._children:
208 result = result and child.SetSyncSpeed(speed)
211 def GetSyncStatus(self):
212 """Returns the sync status of the device.
214 If this device is a mirroring device, this function returns the
215 status of the mirror.
217 If sync_percent is None, it means the device is not syncing.
219 If estimated_time is None, it means we can't estimate
220 the time needed, otherwise it's the time left in seconds.
222 If is_degraded is True, it means the device is missing
223 redundancy. This is usually a sign that something went wrong in
224 the device setup, if sync_percent is None.
226 The ldisk parameter represents the degradation of the local
227 data. This is only valid for some devices, the rest will always
228 return False (not degraded).
231 @return: (sync_percent, estimated_time, is_degraded, ldisk)
234 return None, None, False, False
237 def CombinedSyncStatus(self):
238 """Calculate the mirror status recursively for our children.
240 The return value is the same as for `GetSyncStatus()` except the
241 minimum percent and maximum time are calculated across our
245 min_percent, max_time, is_degraded, ldisk = self.GetSyncStatus()
247 for child in self._children:
248 c_percent, c_time, c_degraded, c_ldisk = child.GetSyncStatus()
249 if min_percent is None:
250 min_percent = c_percent
251 elif c_percent is not None:
252 min_percent = min(min_percent, c_percent)
255 elif c_time is not None:
256 max_time = max(max_time, c_time)
257 is_degraded = is_degraded or c_degraded
258 ldisk = ldisk or c_ldisk
259 return min_percent, max_time, is_degraded, ldisk
262 def SetInfo(self, text):
263 """Update metadata with info text.
265 Only supported for some device types.
268 for child in self._children:
271 def Grow(self, amount):
272 """Grow the block device.
274 @param amount: the amount (in mebibytes) to grow with
277 raise NotImplementedError
280 return ("<%s: unique_id: %s, children: %s, %s:%s, %s>" %
281 (self.__class__, self.unique_id, self._children,
282 self.major, self.minor, self.dev_path))
285 class LogicalVolume(BlockDev):
286 """Logical Volume block device.
289 def __init__(self, unique_id, children):
290 """Attaches to a LV device.
292 The unique_id is a tuple (vg_name, lv_name)
295 super(LogicalVolume, self).__init__(unique_id, children)
296 if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
297 raise ValueError("Invalid configuration data %s" % str(unique_id))
298 self._vg_name, self._lv_name = unique_id
299 self.dev_path = "/dev/%s/%s" % (self._vg_name, self._lv_name)
300 self._degraded = True
301 self.major = self.minor = None
305 def Create(cls, unique_id, children, size):
306 """Create a new logical volume.
309 if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
310 raise errors.ProgrammerError("Invalid configuration data %s" %
312 vg_name, lv_name = unique_id
313 pvs_info = cls.GetPVInfo(vg_name)
315 _ThrowError("Can't compute PV info for vg %s", vg_name)
319 pvlist = [ pv[1] for pv in pvs_info ]
320 free_size = sum([ pv[0] for pv in pvs_info ])
322 # The size constraint should have been checked from the master before
323 # calling the create function.
325 _ThrowError("Not enough free space: required %s,"
326 " available %s", size, free_size)
327 result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-n%s" % lv_name,
330 _ThrowError("LV create failed (%s): %s",
331 result.fail_reason, result.output)
332 return LogicalVolume(unique_id, children)
335 def GetPVInfo(vg_name):
336 """Get the free space info for PVs in a volume group.
338 @param vg_name: the volume group name
341 @return: list of tuples (free_space, name) with free_space in mebibytes
344 command = ["pvs", "--noheadings", "--nosuffix", "--units=m",
345 "-opv_name,vg_name,pv_free,pv_attr", "--unbuffered",
347 result = utils.RunCmd(command)
349 logging.error("Can't get the PV information: %s - %s",
350 result.fail_reason, result.output)
353 for line in result.stdout.splitlines():
354 fields = line.strip().split(':')
356 logging.error("Can't parse pvs output: line '%s'", line)
358 # skip over pvs from another vg or ones which are not allocatable
359 if fields[1] != vg_name or fields[3][0] != 'a':
361 data.append((float(fields[2]), fields[0]))
366 """Remove this logical volume.
369 if not self.minor and not self.Attach():
370 # the LV does not exist
372 result = utils.RunCmd(["lvremove", "-f", "%s/%s" %
373 (self._vg_name, self._lv_name)])
375 _ThrowError("Can't lvremove: %s - %s", result.fail_reason, result.output)
377 def Rename(self, new_id):
378 """Rename this logical volume.
381 if not isinstance(new_id, (tuple, list)) or len(new_id) != 2:
382 raise errors.ProgrammerError("Invalid new logical id '%s'" % new_id)
383 new_vg, new_name = new_id
384 if new_vg != self._vg_name:
385 raise errors.ProgrammerError("Can't move a logical volume across"
386 " volume groups (from %s to to %s)" %
387 (self._vg_name, new_vg))
388 result = utils.RunCmd(["lvrename", new_vg, self._lv_name, new_name])
390 _ThrowError("Failed to rename the logical volume: %s", result.output)
391 self._lv_name = new_name
392 self.dev_path = "/dev/%s/%s" % (self._vg_name, self._lv_name)
395 """Attach to an existing LV.
397 This method will try to see if an existing and active LV exists
398 which matches our name. If so, its major/minor will be
402 self.attached = False
403 result = utils.RunCmd(["lvs", "--noheadings", "--separator=,",
404 "-olv_attr,lv_kernel_major,lv_kernel_minor",
407 logging.error("Can't find LV %s: %s, %s",
408 self.dev_path, result.fail_reason, result.output)
410 out = result.stdout.strip().rstrip(',')
413 logging.error("Can't parse LVS output, len(%s) != 3", str(out))
416 status, major, minor = out[:3]
418 logging.error("lvs lv_attr is not 6 characters (%s)", status)
424 except ValueError, err:
425 logging.error("lvs major/minor cannot be parsed: %s", str(err))
429 self._degraded = status[0] == 'v' # virtual volume, i.e. doesn't backing
435 """Assemble the device.
437 We alway run `lvchange -ay` on the LV to ensure it's active before
438 use, as there were cases when xenvg was not active after boot
439 (also possibly after disk issues).
442 result = utils.RunCmd(["lvchange", "-ay", self.dev_path])
444 _ThrowError("Can't activate lv %s: %s", self.dev_path, result.output)
447 """Shutdown the device.
449 This is a no-op for the LV device type, as we don't deactivate the
455 def GetSyncStatus(self):
456 """Returns the sync status of the device.
458 If this device is a mirroring device, this function returns the
459 status of the mirror.
461 For logical volumes, sync_percent and estimated_time are always
462 None (no recovery in progress, as we don't handle the mirrored LV
463 case). The is_degraded parameter is the inverse of the ldisk
466 For the ldisk parameter, we check if the logical volume has the
467 'virtual' type, which means it's not backed by existing storage
468 anymore (read from it return I/O error). This happens after a
469 physical disk failure and subsequent 'vgreduce --removemissing' on
472 The status was already read in Attach, so we just return it.
475 @return: (sync_percent, estimated_time, is_degraded, ldisk)
478 return None, None, self._degraded, self._degraded
480 def Open(self, force=False):
481 """Make the device ready for I/O.
483 This is a no-op for the LV device type.
489 """Notifies that the device will no longer be used for I/O.
491 This is a no-op for the LV device type.
496 def Snapshot(self, size):
497 """Create a snapshot copy of an lvm block device.
500 snap_name = self._lv_name + ".snap"
502 # remove existing snapshot if found
503 snap = LogicalVolume((self._vg_name, snap_name), None)
504 _IgnoreError(snap.Remove)
506 pvs_info = self.GetPVInfo(self._vg_name)
508 _ThrowError("Can't compute PV info for vg %s", self._vg_name)
511 free_size, pv_name = pvs_info[0]
513 _ThrowError("Not enough free space: required %s,"
514 " available %s", size, free_size)
516 result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-s",
517 "-n%s" % snap_name, self.dev_path])
519 _ThrowError("command: %s error: %s - %s",
520 result.cmd, result.fail_reason, result.output)
524 def SetInfo(self, text):
525 """Update metadata with info text.
528 BlockDev.SetInfo(self, text)
530 # Replace invalid characters
531 text = re.sub('^[^A-Za-z0-9_+.]', '_', text)
532 text = re.sub('[^-A-Za-z0-9_+.]', '_', text)
534 # Only up to 128 characters are allowed
537 result = utils.RunCmd(["lvchange", "--addtag", text,
540 _ThrowError("Command: %s error: %s - %s", result.cmd, result.fail_reason,
543 def Grow(self, amount):
544 """Grow the logical volume.
547 # we try multiple algorithms since the 'best' ones might not have
548 # space available in the right place, but later ones might (since
549 # they have less constraints); also note that only recent LVM
551 for alloc_policy in "contiguous", "cling", "normal":
552 result = utils.RunCmd(["lvextend", "--alloc", alloc_policy,
553 "-L", "+%dm" % amount, self.dev_path])
554 if not result.failed:
556 _ThrowError("Can't grow LV %s: %s", self.dev_path, result.output)
559 class DRBD8Status(object):
560 """A DRBD status representation class.
562 Note that this doesn't support unconfigured devices (cs:Unconfigured).
565 UNCONF_RE = re.compile(r"\s*[0-9]+:\s*cs:Unconfigured$")
566 LINE_RE = re.compile(r"\s*[0-9]+:\s*cs:(\S+)\s+st:([^/]+)/(\S+)"
567 "\s+ds:([^/]+)/(\S+)\s+.*$")
568 SYNC_RE = re.compile(r"^.*\ssync'ed:\s*([0-9.]+)%.*"
569 "\sfinish: ([0-9]+):([0-9]+):([0-9]+)\s.*$")
571 def __init__(self, procline):
572 u = self.UNCONF_RE.match(procline)
574 self.cstatus = "Unconfigured"
575 self.lrole = self.rrole = self.ldisk = self.rdisk = None
577 m = self.LINE_RE.match(procline)
579 raise errors.BlockDeviceError("Can't parse input data '%s'" % procline)
580 self.cstatus = m.group(1)
581 self.lrole = m.group(2)
582 self.rrole = m.group(3)
583 self.ldisk = m.group(4)
584 self.rdisk = m.group(5)
586 # end reading of data from the LINE_RE or UNCONF_RE
588 self.is_standalone = self.cstatus == "StandAlone"
589 self.is_wfconn = self.cstatus == "WFConnection"
590 self.is_connected = self.cstatus == "Connected"
591 self.is_primary = self.lrole == "Primary"
592 self.is_secondary = self.lrole == "Secondary"
593 self.peer_primary = self.rrole == "Primary"
594 self.peer_secondary = self.rrole == "Secondary"
595 self.both_primary = self.is_primary and self.peer_primary
596 self.both_secondary = self.is_secondary and self.peer_secondary
598 self.is_diskless = self.ldisk == "Diskless"
599 self.is_disk_uptodate = self.ldisk == "UpToDate"
601 self.is_in_resync = self.cstatus in ("SyncSource", "SyncTarget")
602 self.is_in_use = self.cstatus != "Unconfigured"
604 m = self.SYNC_RE.match(procline)
606 self.sync_percent = float(m.group(1))
607 hours = int(m.group(2))
608 minutes = int(m.group(3))
609 seconds = int(m.group(4))
610 self.est_time = hours * 3600 + minutes * 60 + seconds
612 self.sync_percent = None
615 self.is_sync_target = self.peer_sync_source = self.cstatus == "SyncTarget"
616 self.peer_sync_target = self.is_sync_source = self.cstatus == "SyncSource"
617 self.is_resync = self.is_sync_target or self.is_sync_source
620 class BaseDRBD(BlockDev):
623 This class contains a few bits of common functionality between the
624 0.7 and 8.x versions of DRBD.
627 _VERSION_RE = re.compile(r"^version: (\d+)\.(\d+)\.(\d+)"
628 r" \(api:(\d+)/proto:(\d+)(?:-(\d+))?\)")
631 _ST_UNCONFIGURED = "Unconfigured"
632 _ST_WFCONNECTION = "WFConnection"
633 _ST_CONNECTED = "Connected"
635 _STATUS_FILE = "/proc/drbd"
638 def _GetProcData(filename=_STATUS_FILE):
639 """Return data from /proc/drbd.
643 stat = open(filename, "r")
645 data = stat.read().splitlines()
648 except EnvironmentError, err:
649 if err.errno == errno.ENOENT:
650 _ThrowError("The file %s cannot be opened, check if the module"
651 " is loaded (%s)", filename, str(err))
653 _ThrowError("Can't read the DRBD proc file %s: %s", filename, str(err))
655 _ThrowError("Can't read any data from %s", filename)
659 def _MassageProcData(data):
660 """Transform the output of _GetProdData into a nicer form.
662 @return: a dictionary of minor: joined lines from /proc/drbd
666 lmatch = re.compile("^ *([0-9]+):.*$")
668 old_minor = old_line = None
670 lresult = lmatch.match(line)
671 if lresult is not None:
672 if old_minor is not None:
673 results[old_minor] = old_line
674 old_minor = int(lresult.group(1))
677 if old_minor is not None:
678 old_line += " " + line.strip()
680 if old_minor is not None:
681 results[old_minor] = old_line
685 def _GetVersion(cls):
686 """Return the DRBD version.
688 This will return a dict with keys:
694 - proto2 (only on drbd > 8.2.X)
697 proc_data = cls._GetProcData()
698 first_line = proc_data[0].strip()
699 version = cls._VERSION_RE.match(first_line)
701 raise errors.BlockDeviceError("Can't parse DRBD version from '%s'" %
704 values = version.groups()
705 retval = {'k_major': int(values[0]),
706 'k_minor': int(values[1]),
707 'k_point': int(values[2]),
708 'api': int(values[3]),
709 'proto': int(values[4]),
711 if values[5] is not None:
712 retval['proto2'] = values[5]
718 """Return the path to a drbd device for a given minor.
721 return "/dev/drbd%d" % minor
724 def GetUsedDevs(cls):
725 """Compute the list of used DRBD devices.
728 data = cls._GetProcData()
731 valid_line = re.compile("^ *([0-9]+): cs:([^ ]+).*$")
733 match = valid_line.match(line)
736 minor = int(match.group(1))
737 state = match.group(2)
738 if state == cls._ST_UNCONFIGURED:
740 used_devs[minor] = state, line
744 def _SetFromMinor(self, minor):
745 """Set our parameters based on the given minor.
747 This sets our minor variable and our dev_path.
751 self.minor = self.dev_path = None
752 self.attached = False
755 self.dev_path = self._DevPath(minor)
759 def _CheckMetaSize(meta_device):
760 """Check if the given meta device looks like a valid one.
762 This currently only check the size, which must be around
766 result = utils.RunCmd(["blockdev", "--getsize", meta_device])
768 _ThrowError("Failed to get device size: %s - %s",
769 result.fail_reason, result.output)
771 sectors = int(result.stdout)
773 _ThrowError("Invalid output from blockdev: '%s'", result.stdout)
774 bytes = sectors * 512
775 if bytes < 128 * 1024 * 1024: # less than 128MiB
776 _ThrowError("Meta device too small (%.2fMib)", (bytes / 1024 / 1024))
777 if bytes > (128 + 32) * 1024 * 1024: # account for an extra (big) PE on LVM
778 _ThrowError("Meta device too big (%.2fMiB)", (bytes / 1024 / 1024))
780 def Rename(self, new_id):
783 This is not supported for drbd devices.
786 raise errors.ProgrammerError("Can't rename a drbd device")
789 class DRBD8(BaseDRBD):
790 """DRBD v8.x block device.
792 This implements the local host part of the DRBD device, i.e. it
793 doesn't do anything to the supposed peer. If you need a fully
794 connected DRBD pair, you need to use this class on both hosts.
796 The unique_id for the drbd device is the (local_ip, local_port,
797 remote_ip, remote_port) tuple, and it must have two children: the
798 data device and the meta_device. The meta device is checked for
799 valid size and is zeroed on create.
806 _NET_RECONFIG_TIMEOUT = 60
808 def __init__(self, unique_id, children):
809 if children and children.count(None) > 0:
811 super(DRBD8, self).__init__(unique_id, children)
812 self.major = self._DRBD_MAJOR
813 version = self._GetVersion()
814 if version['k_major'] != 8 :
815 _ThrowError("Mismatch in DRBD kernel version and requested ganeti"
816 " usage: kernel is %s.%s, ganeti wants 8.x",
817 version['k_major'], version['k_minor'])
819 if len(children) not in (0, 2):
820 raise ValueError("Invalid configuration data %s" % str(children))
821 if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 6:
822 raise ValueError("Invalid configuration data %s" % str(unique_id))
823 (self._lhost, self._lport,
824 self._rhost, self._rport,
825 self._aminor, self._secret) = unique_id
826 if (self._lhost is not None and self._lhost == self._rhost and
827 self._lport == self._rport):
828 raise ValueError("Invalid configuration data, same local/remote %s" %
833 def _InitMeta(cls, minor, dev_path):
834 """Initialize a meta device.
836 This will not work if the given minor is in use.
839 result = utils.RunCmd(["drbdmeta", "--force", cls._DevPath(minor),
840 "v08", dev_path, "0", "create-md"])
842 _ThrowError("Can't initialize meta device: %s", result.output)
845 def _FindUnusedMinor(cls):
846 """Find an unused DRBD device.
848 This is specific to 8.x as the minors are allocated dynamically,
849 so non-existing numbers up to a max minor count are actually free.
852 data = cls._GetProcData()
854 unused_line = re.compile("^ *([0-9]+): cs:Unconfigured$")
855 used_line = re.compile("^ *([0-9]+): cs:")
858 match = unused_line.match(line)
860 return int(match.group(1))
861 match = used_line.match(line)
863 minor = int(match.group(1))
864 highest = max(highest, minor)
865 if highest is None: # there are no minors in use at all
867 if highest >= cls._MAX_MINORS:
868 logging.error("Error: no free drbd minors!")
869 raise errors.BlockDeviceError("Can't find a free DRBD minor")
873 def _GetShowParser(cls):
874 """Return a parser for `drbd show` output.
876 This will either create or return an already-create parser for the
877 output of the command `drbd show`.
880 if cls._PARSE_SHOW is not None:
881 return cls._PARSE_SHOW
884 lbrace = pyp.Literal("{").suppress()
885 rbrace = pyp.Literal("}").suppress()
886 semi = pyp.Literal(";").suppress()
887 # this also converts the value to an int
888 number = pyp.Word(pyp.nums).setParseAction(lambda s, l, t: int(t[0]))
890 comment = pyp.Literal ("#") + pyp.Optional(pyp.restOfLine)
891 defa = pyp.Literal("_is_default").suppress()
892 dbl_quote = pyp.Literal('"').suppress()
894 keyword = pyp.Word(pyp.alphanums + '-')
897 value = pyp.Word(pyp.alphanums + '_-/.:')
898 quoted = dbl_quote + pyp.CharsNotIn('"') + dbl_quote
899 addr_type = (pyp.Optional(pyp.Literal("ipv4")).suppress() +
900 pyp.Optional(pyp.Literal("ipv6")).suppress())
901 addr_port = (addr_type + pyp.Word(pyp.nums + '.') +
902 pyp.Literal(':').suppress() + number)
903 # meta device, extended syntax
904 meta_value = ((value ^ quoted) + pyp.Literal('[').suppress() +
905 number + pyp.Word(']').suppress())
908 stmt = (~rbrace + keyword + ~lbrace +
909 pyp.Optional(addr_port ^ value ^ quoted ^ meta_value) +
910 pyp.Optional(defa) + semi +
911 pyp.Optional(pyp.restOfLine).suppress())
914 section_name = pyp.Word(pyp.alphas + '_')
915 section = section_name + lbrace + pyp.ZeroOrMore(pyp.Group(stmt)) + rbrace
917 bnf = pyp.ZeroOrMore(pyp.Group(section ^ stmt))
920 cls._PARSE_SHOW = bnf
925 def _GetShowData(cls, minor):
926 """Return the `drbdsetup show` data for a minor.
929 result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "show"])
931 logging.error("Can't display the drbd config: %s - %s",
932 result.fail_reason, result.output)
937 def _GetDevInfo(cls, out):
938 """Parse details about a given DRBD minor.
940 This return, if available, the local backing device (as a path)
941 and the local and remote (ip, port) information from a string
942 containing the output of the `drbdsetup show` command as returned
950 bnf = cls._GetShowParser()
954 results = bnf.parseString(out)
955 except pyp.ParseException, err:
956 _ThrowError("Can't parse drbdsetup show output: %s", str(err))
958 # and massage the results into our desired format
959 for section in results:
961 if sname == "_this_host":
962 for lst in section[1:]:
964 data["local_dev"] = lst[1]
965 elif lst[0] == "meta-disk":
966 data["meta_dev"] = lst[1]
967 data["meta_index"] = lst[2]
968 elif lst[0] == "address":
969 data["local_addr"] = tuple(lst[1:])
970 elif sname == "_remote_host":
971 for lst in section[1:]:
972 if lst[0] == "address":
973 data["remote_addr"] = tuple(lst[1:])
976 def _MatchesLocal(self, info):
977 """Test if our local config matches with an existing device.
979 The parameter should be as returned from `_GetDevInfo()`. This
980 method tests if our local backing device is the same as the one in
981 the info parameter, in effect testing if we look like the given
986 backend, meta = self._children
988 backend = meta = None
990 if backend is not None:
991 retval = ("local_dev" in info and info["local_dev"] == backend.dev_path)
993 retval = ("local_dev" not in info)
996 retval = retval and ("meta_dev" in info and
997 info["meta_dev"] == meta.dev_path)
998 retval = retval and ("meta_index" in info and
999 info["meta_index"] == 0)
1001 retval = retval and ("meta_dev" not in info and
1002 "meta_index" not in info)
1005 def _MatchesNet(self, info):
1006 """Test if our network config matches with an existing device.
1008 The parameter should be as returned from `_GetDevInfo()`. This
1009 method tests if our network configuration is the same as the one
1010 in the info parameter, in effect testing if we look like the given
1014 if (((self._lhost is None and not ("local_addr" in info)) and
1015 (self._rhost is None and not ("remote_addr" in info)))):
1018 if self._lhost is None:
1021 if not ("local_addr" in info and
1022 "remote_addr" in info):
1025 retval = (info["local_addr"] == (self._lhost, self._lport))
1026 retval = (retval and
1027 info["remote_addr"] == (self._rhost, self._rport))
1031 def _AssembleLocal(cls, minor, backend, meta):
1032 """Configure the local part of a DRBD device.
1035 args = ["drbdsetup", cls._DevPath(minor), "disk",
1036 backend, meta, "0", "-e", "detach", "--create-device"]
1037 result = utils.RunCmd(args)
1039 _ThrowError("drbd%d: can't attach local disk: %s", minor, result.output)
1042 def _AssembleNet(cls, minor, net_info, protocol,
1043 dual_pri=False, hmac=None, secret=None):
1044 """Configure the network part of the device.
1047 lhost, lport, rhost, rport = net_info
1048 if None in net_info:
1049 # we don't want network connection and actually want to make
1051 cls._ShutdownNet(minor)
1054 # Workaround for a race condition. When DRBD is doing its dance to
1055 # establish a connection with its peer, it also sends the
1056 # synchronization speed over the wire. In some cases setting the
1057 # sync speed only after setting up both sides can race with DRBD
1058 # connecting, hence we set it here before telling DRBD anything
1060 cls._SetMinorSyncSpeed(minor, constants.SYNC_SPEED)
1062 args = ["drbdsetup", cls._DevPath(minor), "net",
1063 "%s:%s" % (lhost, lport), "%s:%s" % (rhost, rport), protocol,
1064 "-A", "discard-zero-changes",
1071 args.extend(["-a", hmac, "-x", secret])
1072 result = utils.RunCmd(args)
1074 _ThrowError("drbd%d: can't setup network: %s - %s",
1075 minor, result.fail_reason, result.output)
1077 timeout = time.time() + 10
1079 while time.time() < timeout:
1080 info = cls._GetDevInfo(cls._GetShowData(minor))
1081 if not "local_addr" in info or not "remote_addr" in info:
1084 if (info["local_addr"] != (lhost, lport) or
1085 info["remote_addr"] != (rhost, rport)):
1091 _ThrowError("drbd%d: timeout while configuring network", minor)
1093 def AddChildren(self, devices):
1094 """Add a disk to the DRBD device.
1097 if self.minor is None:
1098 _ThrowError("drbd%d: can't attach to dbrd8 during AddChildren",
1100 if len(devices) != 2:
1101 _ThrowError("drbd%d: need two devices for AddChildren", self.minor)
1102 info = self._GetDevInfo(self._GetShowData(self.minor))
1103 if "local_dev" in info:
1104 _ThrowError("drbd%d: already attached to a local disk", self.minor)
1105 backend, meta = devices
1106 if backend.dev_path is None or meta.dev_path is None:
1107 _ThrowError("drbd%d: children not ready during AddChildren", self.minor)
1110 self._CheckMetaSize(meta.dev_path)
1111 self._InitMeta(self._FindUnusedMinor(), meta.dev_path)
1113 self._AssembleLocal(self.minor, backend.dev_path, meta.dev_path)
1114 self._children = devices
1116 def RemoveChildren(self, devices):
1117 """Detach the drbd device from local storage.
1120 if self.minor is None:
1121 _ThrowError("drbd%d: can't attach to drbd8 during RemoveChildren",
1123 # early return if we don't actually have backing storage
1124 info = self._GetDevInfo(self._GetShowData(self.minor))
1125 if "local_dev" not in info:
1127 if len(self._children) != 2:
1128 _ThrowError("drbd%d: we don't have two children: %s", self.minor,
1130 if self._children.count(None) == 2: # we don't actually have children :)
1131 logging.warning("drbd%d: requested detach while detached", self.minor)
1133 if len(devices) != 2:
1134 _ThrowError("drbd%d: we need two children in RemoveChildren", self.minor)
1135 for child, dev in zip(self._children, devices):
1136 if dev != child.dev_path:
1137 _ThrowError("drbd%d: mismatch in local storage (%s != %s) in"
1138 " RemoveChildren", self.minor, dev, child.dev_path)
1140 self._ShutdownLocal(self.minor)
1144 def _SetMinorSyncSpeed(cls, minor, kbytes):
1145 """Set the speed of the DRBD syncer.
1147 This is the low-level implementation.
1150 @param minor: the drbd minor whose settings we change
1152 @param kbytes: the speed in kbytes/second
1154 @return: the success of the operation
1157 result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "syncer",
1158 "-r", "%d" % kbytes, "--create-device"])
1160 logging.error("Can't change syncer rate: %s - %s",
1161 result.fail_reason, result.output)
1162 return not result.failed
1164 def SetSyncSpeed(self, kbytes):
1165 """Set the speed of the DRBD syncer.
1168 @param kbytes: the speed in kbytes/second
1170 @return: the success of the operation
1173 if self.minor is None:
1174 logging.info("Not attached during SetSyncSpeed")
1176 children_result = super(DRBD8, self).SetSyncSpeed(kbytes)
1177 return self._SetMinorSyncSpeed(self.minor, kbytes) and children_result
1179 def GetProcStatus(self):
1180 """Return device data from /proc.
1183 if self.minor is None:
1184 _ThrowError("drbd%d: GetStats() called while not attached", self._aminor)
1185 proc_info = self._MassageProcData(self._GetProcData())
1186 if self.minor not in proc_info:
1187 _ThrowError("drbd%d: can't find myself in /proc", self.minor)
1188 return DRBD8Status(proc_info[self.minor])
1190 def GetSyncStatus(self):
1191 """Returns the sync status of the device.
1194 If sync_percent is None, it means all is ok
1195 If estimated_time is None, it means we can't esimate
1196 the time needed, otherwise it's the time left in seconds.
1199 We set the is_degraded parameter to True on two conditions:
1200 network not connected or local disk missing.
1202 We compute the ldisk parameter based on wheter we have a local
1206 @return: (sync_percent, estimated_time, is_degraded, ldisk)
1209 if self.minor is None and not self.Attach():
1210 _ThrowError("drbd%d: can't Attach() in GetSyncStatus", self._aminor)
1211 stats = self.GetProcStatus()
1212 ldisk = not stats.is_disk_uptodate
1213 is_degraded = not stats.is_connected
1214 return stats.sync_percent, stats.est_time, is_degraded or ldisk, ldisk
1216 def Open(self, force=False):
1217 """Make the local state primary.
1219 If the 'force' parameter is given, the '-o' option is passed to
1220 drbdsetup. Since this is a potentially dangerous operation, the
1221 force flag should be only given after creation, when it actually
1225 if self.minor is None and not self.Attach():
1226 logging.error("DRBD cannot attach to a device during open")
1228 cmd = ["drbdsetup", self.dev_path, "primary"]
1231 result = utils.RunCmd(cmd)
1233 _ThrowError("drbd%d: can't make drbd device primary: %s", self.minor,
1237 """Make the local state secondary.
1239 This will, of course, fail if the device is in use.
1242 if self.minor is None and not self.Attach():
1243 _ThrowError("drbd%d: can't Attach() in Close()", self._aminor)
1244 result = utils.RunCmd(["drbdsetup", self.dev_path, "secondary"])
1246 _ThrowError("drbd%d: can't switch drbd device to secondary: %s",
1247 self.minor, result.output)
1249 def DisconnectNet(self):
1250 """Removes network configuration.
1252 This method shutdowns the network side of the device.
1254 The method will wait up to a hardcoded timeout for the device to
1255 go into standalone after the 'disconnect' command before
1256 re-configuring it, as sometimes it takes a while for the
1257 disconnect to actually propagate and thus we might issue a 'net'
1258 command while the device is still connected. If the device will
1259 still be attached to the network and we time out, we raise an
1263 if self.minor is None:
1264 _ThrowError("drbd%d: disk not attached in re-attach net", self._aminor)
1266 if None in (self._lhost, self._lport, self._rhost, self._rport):
1267 _ThrowError("drbd%d: DRBD disk missing network info in"
1268 " DisconnectNet()", self.minor)
1270 ever_disconnected = _IgnoreError(self._ShutdownNet, self.minor)
1271 timeout_limit = time.time() + self._NET_RECONFIG_TIMEOUT
1272 sleep_time = 0.100 # we start the retry time at 100 miliseconds
1273 while time.time() < timeout_limit:
1274 status = self.GetProcStatus()
1275 if status.is_standalone:
1277 # retry the disconnect, it seems possible that due to a
1278 # well-time disconnect on the peer, my disconnect command might
1279 # be ingored and forgotten
1280 ever_disconnected = _IgnoreError(self._ShutdownNet, self.minor) or \
1282 time.sleep(sleep_time)
1283 sleep_time = min(2, sleep_time * 1.5)
1285 if not status.is_standalone:
1286 if ever_disconnected:
1287 msg = ("drbd%d: device did not react to the"
1288 " 'disconnect' command in a timely manner")
1290 msg = "drbd%d: can't shutdown network, even after multiple retries"
1291 _ThrowError(msg, self.minor)
1293 reconfig_time = time.time() - timeout_limit + self._NET_RECONFIG_TIMEOUT
1294 if reconfig_time > 15: # hardcoded alert limit
1295 logging.info("drbd%d: DisconnectNet: detach took %.3f seconds",
1296 self.minor, reconfig_time)
1298 def AttachNet(self, multimaster):
1299 """Reconnects the network.
1301 This method connects the network side of the device with a
1302 specified multi-master flag. The device needs to be 'Standalone'
1303 but have valid network configuration data.
1306 - multimaster: init the network in dual-primary mode
1309 if self.minor is None:
1310 _ThrowError("drbd%d: device not attached in AttachNet", self._aminor)
1312 if None in (self._lhost, self._lport, self._rhost, self._rport):
1313 _ThrowError("drbd%d: missing network info in AttachNet()", self.minor)
1315 status = self.GetProcStatus()
1317 if not status.is_standalone:
1318 _ThrowError("drbd%d: device is not standalone in AttachNet", self.minor)
1320 self._AssembleNet(self.minor,
1321 (self._lhost, self._lport, self._rhost, self._rport),
1322 constants.DRBD_NET_PROTOCOL, dual_pri=multimaster,
1323 hmac=constants.DRBD_HMAC_ALG, secret=self._secret)
1326 """Check if our minor is configured.
1328 This doesn't do any device configurations - it only checks if the
1329 minor is in a state different from Unconfigured.
1331 Note that this function will not change the state of the system in
1332 any way (except in case of side-effects caused by reading from
1336 used_devs = self.GetUsedDevs()
1337 if self._aminor in used_devs:
1338 minor = self._aminor
1342 self._SetFromMinor(minor)
1343 return minor is not None
1346 """Assemble the drbd.
1349 - if we have a configured device, we try to ensure that it matches
1351 - if not, we create it from zero
1354 super(DRBD8, self).Assemble()
1357 if self.minor is None:
1358 # local device completely unconfigured
1359 self._FastAssemble()
1361 # we have to recheck the local and network status and try to fix
1363 self._SlowAssemble()
1365 def _SlowAssemble(self):
1366 """Assembles the DRBD device from a (partially) configured device.
1368 In case of partially attached (local device matches but no network
1369 setup), we perform the network attach. If successful, we re-test
1370 the attach if can return success.
1373 net_data = (self._lhost, self._lport, self._rhost, self._rport)
1374 for minor in (self._aminor,):
1375 info = self._GetDevInfo(self._GetShowData(minor))
1376 match_l = self._MatchesLocal(info)
1377 match_r = self._MatchesNet(info)
1379 if match_l and match_r:
1380 # everything matches
1383 if match_l and not match_r and "local_addr" not in info:
1384 # disk matches, but not attached to network, attach and recheck
1385 self._AssembleNet(minor, net_data, constants.DRBD_NET_PROTOCOL,
1386 hmac=constants.DRBD_HMAC_ALG, secret=self._secret)
1387 if self._MatchesNet(self._GetDevInfo(self._GetShowData(minor))):
1390 _ThrowError("drbd%d: network attach successful, but 'drbdsetup"
1391 " show' disagrees", minor)
1393 if match_r and "local_dev" not in info:
1394 # no local disk, but network attached and it matches
1395 self._AssembleLocal(minor, self._children[0].dev_path,
1396 self._children[1].dev_path)
1397 if self._MatchesNet(self._GetDevInfo(self._GetShowData(minor))):
1400 _ThrowError("drbd%d: disk attach successful, but 'drbdsetup"
1401 " show' disagrees", minor)
1403 # this case must be considered only if we actually have local
1404 # storage, i.e. not in diskless mode, because all diskless
1405 # devices are equal from the point of view of local
1407 if (match_l and "local_dev" in info and
1408 not match_r and "local_addr" in info):
1409 # strange case - the device network part points to somewhere
1410 # else, even though its local storage is ours; as we own the
1411 # drbd space, we try to disconnect from the remote peer and
1412 # reconnect to our correct one
1414 self._ShutdownNet(minor)
1415 except errors.BlockDeviceError, err:
1416 _ThrowError("drbd%d: device has correct local storage, wrong"
1417 " remote peer and is unable to disconnect in order"
1418 " to attach to the correct peer: %s", minor, str(err))
1419 # note: _AssembleNet also handles the case when we don't want
1420 # local storage (i.e. one or more of the _[lr](host|port) is
1422 self._AssembleNet(minor, net_data, constants.DRBD_NET_PROTOCOL,
1423 hmac=constants.DRBD_HMAC_ALG, secret=self._secret)
1424 if self._MatchesNet(self._GetDevInfo(self._GetShowData(minor))):
1427 _ThrowError("drbd%d: network attach successful, but 'drbdsetup"
1428 " show' disagrees", minor)
1433 self._SetFromMinor(minor)
1435 _ThrowError("drbd%d: cannot activate, unknown or unhandled reason",
1438 def _FastAssemble(self):
1439 """Assemble the drbd device from zero.
1441 This is run when in Assemble we detect our minor is unused.
1444 minor = self._aminor
1445 if self._children and self._children[0] and self._children[1]:
1446 self._AssembleLocal(minor, self._children[0].dev_path,
1447 self._children[1].dev_path)
1448 if self._lhost and self._lport and self._rhost and self._rport:
1449 self._AssembleNet(minor,
1450 (self._lhost, self._lport, self._rhost, self._rport),
1451 constants.DRBD_NET_PROTOCOL,
1452 hmac=constants.DRBD_HMAC_ALG, secret=self._secret)
1453 self._SetFromMinor(minor)
1456 def _ShutdownLocal(cls, minor):
1457 """Detach from the local device.
1459 I/Os will continue to be served from the remote device. If we
1460 don't have a remote device, this operation will fail.
1463 result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "detach"])
1465 _ThrowError("drbd%d: can't detach local disk: %s", minor, result.output)
1468 def _ShutdownNet(cls, minor):
1469 """Disconnect from the remote peer.
1471 This fails if we don't have a local device.
1474 result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disconnect"])
1476 _ThrowError("drbd%d: can't shutdown network: %s", minor, result.output)
1479 def _ShutdownAll(cls, minor):
1480 """Deactivate the device.
1482 This will, of course, fail if the device is in use.
1485 result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "down"])
1487 _ThrowError("drbd%d: can't shutdown drbd device: %s",
1488 minor, result.output)
1491 """Shutdown the DRBD device.
1494 if self.minor is None and not self.Attach():
1495 logging.info("drbd%d: not attached during Shutdown()", self._aminor)
1499 self.dev_path = None
1500 self._ShutdownAll(minor)
1503 """Stub remove for DRBD devices.
1509 def Create(cls, unique_id, children, size):
1510 """Create a new DRBD8 device.
1512 Since DRBD devices are not created per se, just assembled, this
1513 function only initializes the metadata.
1516 if len(children) != 2:
1517 raise errors.ProgrammerError("Invalid setup for the drbd device")
1518 # check that the minor is unused
1519 aminor = unique_id[4]
1520 proc_info = cls._MassageProcData(cls._GetProcData())
1521 if aminor in proc_info:
1522 status = DRBD8Status(proc_info[aminor])
1523 in_use = status.is_in_use
1527 _ThrowError("drbd%d: minor is already in use at Create() time", aminor)
1530 if not meta.Attach():
1531 _ThrowError("drbd%d: can't attach to meta device '%s'",
1533 cls._CheckMetaSize(meta.dev_path)
1534 cls._InitMeta(aminor, meta.dev_path)
1535 return cls(unique_id, children)
1537 def Grow(self, amount):
1538 """Resize the DRBD device and its backing storage.
1541 if self.minor is None:
1542 _ThrowError("drbd%d: Grow called while not attached", self._aminor)
1543 if len(self._children) != 2 or None in self._children:
1544 _ThrowError("drbd%d: cannot grow diskless device", self.minor)
1545 self._children[0].Grow(amount)
1546 result = utils.RunCmd(["drbdsetup", self.dev_path, "resize"])
1548 _ThrowError("drbd%d: resize failed: %s", self.minor, result.output)
1551 class FileStorage(BlockDev):
1554 This class represents the a file storage backend device.
1556 The unique_id for the file device is a (file_driver, file_path) tuple.
1559 def __init__(self, unique_id, children):
1560 """Initalizes a file device backend.
1564 raise errors.BlockDeviceError("Invalid setup for file device")
1565 super(FileStorage, self).__init__(unique_id, children)
1566 if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
1567 raise ValueError("Invalid configuration data %s" % str(unique_id))
1568 self.driver = unique_id[0]
1569 self.dev_path = unique_id[1]
1573 """Assemble the device.
1575 Checks whether the file device exists, raises BlockDeviceError otherwise.
1578 if not os.path.exists(self.dev_path):
1579 _ThrowError("File device '%s' does not exist" % self.dev_path)
1582 """Shutdown the device.
1584 This is a no-op for the file type, as we don't deacivate
1585 the file on shutdown.
1590 def Open(self, force=False):
1591 """Make the device ready for I/O.
1593 This is a no-op for the file type.
1599 """Notifies that the device will no longer be used for I/O.
1601 This is a no-op for the file type.
1607 """Remove the file backing the block device.
1610 @return: True if the removal was successful
1614 os.remove(self.dev_path)
1615 except OSError, err:
1616 if err.errno != errno.ENOENT:
1617 _ThrowError("Can't remove file '%s': %s", self.dev_path, err)
1620 """Attach to an existing file.
1622 Check if this file already exists.
1625 @return: True if file exists
1628 self.attached = os.path.exists(self.dev_path)
1629 return self.attached
1632 def Create(cls, unique_id, children, size):
1633 """Create a new file.
1635 @param size: the size of file in MiB
1637 @rtype: L{bdev.FileStorage}
1638 @return: an instance of FileStorage
1641 if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
1642 raise ValueError("Invalid configuration data %s" % str(unique_id))
1643 dev_path = unique_id[1]
1644 if os.path.exists(dev_path):
1645 _ThrowError("File already existing: %s", dev_path)
1647 f = open(dev_path, 'w')
1648 f.truncate(size * 1024 * 1024)
1650 except IOError, err:
1651 _ThrowError("Error in file creation: %", str(err))
1653 return FileStorage(unique_id, children)
1657 constants.LD_LV: LogicalVolume,
1658 constants.LD_DRBD8: DRBD8,
1659 constants.LD_FILE: FileStorage,
1663 def FindDevice(dev_type, unique_id, children):
1664 """Search for an existing, assembled device.
1666 This will succeed only if the device exists and is assembled, but it
1667 does not do any actions in order to activate the device.
1670 if dev_type not in DEV_MAP:
1671 raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type)
1672 device = DEV_MAP[dev_type](unique_id, children)
1673 if not device.attached:
1678 def Assemble(dev_type, unique_id, children):
1679 """Try to attach or assemble an existing device.
1681 This will attach to assemble the device, as needed, to bring it
1682 fully up. It must be safe to run on already-assembled devices.
1685 if dev_type not in DEV_MAP:
1686 raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type)
1687 device = DEV_MAP[dev_type](unique_id, children)
1692 def Create(dev_type, unique_id, children, size):
1696 if dev_type not in DEV_MAP:
1697 raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type)
1698 device = DEV_MAP[dev_type].Create(unique_id, children, size)