def Assemble(self):
"""Assemble the device from its components.
- If this is a plain block device (e.g. LVM) than assemble does
- nothing, as the LVM has no children and we don't put logical
- volumes offline.
-
- One guarantee is that after the device has been assembled, it
- knows its major/minor numbers. This allows other devices (usually
- parents) to probe correctly for their children.
+ Implementations of this method by child classes must ensure that:
+ - after the device has been assembled, it knows its major/minor
+ numbers; this allows other devices (usually parents) to probe
+ correctly for their children
+ - calling this method on an existing, in-use device is safe
+ - if the device is already configured (and in an OK state),
+ this method is idempotent
"""
- status = True
- for child in self._children:
- if not isinstance(child, BlockDev):
- raise TypeError("Invalid child passed of type '%s'" % type(child))
- if not status:
- break
- status = status and child.Assemble()
- if not status:
- break
-
- try:
- child.Open()
- except errors.BlockDeviceError:
- for child in self._children:
- child.Shutdown()
- raise
-
- if not status:
- for child in self._children:
- child.Shutdown()
- return status
+ return True
def Attach(self):
"""Find a device which matches our config and attach to it.
"""
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
- raise ValueError("Invalid configuration data %s" % str(unique_id))
+ raise errors.ProgrammerError("Invalid configuration data %s" %
+ str(unique_id))
vg_name, lv_name = unique_id
pvs_info = cls.GetPVInfo(vg_name)
if not pvs_info:
result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-n%s" % lv_name,
vg_name] + pvlist)
if result.failed:
- raise errors.BlockDeviceError("%s - %s" % (result.fail_reason,
- result.output))
+ raise errors.BlockDeviceError("LV create failed (%s): %s" %
+ (result.fail_reason, result.output))
return LogicalVolume(unique_id, children)
@staticmethod
Note that this doesn't support unconfigured devices (cs:Unconfigured).
"""
+ UNCONF_RE = re.compile(r"\s*[0-9]+:\s*cs:Unconfigured$")
LINE_RE = re.compile(r"\s*[0-9]+:\s*cs:(\S+)\s+st:([^/]+)/(\S+)"
"\s+ds:([^/]+)/(\S+)\s+.*$")
SYNC_RE = re.compile(r"^.*\ssync'ed:\s*([0-9.]+)%.*"
"\sfinish: ([0-9]+):([0-9]+):([0-9]+)\s.*$")
def __init__(self, procline):
- m = self.LINE_RE.match(procline)
- if not m:
- raise errors.BlockDeviceError("Can't parse input data '%s'" % procline)
- self.cstatus = m.group(1)
- self.lrole = m.group(2)
- self.rrole = m.group(3)
- self.ldisk = m.group(4)
- self.rdisk = m.group(5)
+ u = self.UNCONF_RE.match(procline)
+ if u:
+ self.cstatus = "Unconfigured"
+ self.lrole = self.rrole = self.ldisk = self.rdisk = None
+ else:
+ m = self.LINE_RE.match(procline)
+ if not m:
+ raise errors.BlockDeviceError("Can't parse input data '%s'" % procline)
+ self.cstatus = m.group(1)
+ self.lrole = m.group(2)
+ self.rrole = m.group(3)
+ self.ldisk = m.group(4)
+ self.rdisk = m.group(5)
+
+ # end reading of data from the LINE_RE or UNCONF_RE
self.is_standalone = self.cstatus == "StandAlone"
self.is_wfconn = self.cstatus == "WFConnection"
self.is_diskless = self.ldisk == "Diskless"
self.is_disk_uptodate = self.ldisk == "UpToDate"
+ self.is_in_resync = self.cstatus in ("SyncSource", "SyncTarget")
+ self.is_in_use = self.cstatus != "Unconfigured"
+
m = self.SYNC_RE.match(procline)
if m:
self.sync_percent = float(m.group(1))
return "/dev/drbd%d" % minor
@classmethod
- def _GetUsedDevs(cls):
+ def GetUsedDevs(cls):
"""Compute the list of used DRBD devices.
"""
_MAX_MINORS = 255
_PARSE_SHOW = None
+ # timeout constants
+ _NET_RECONFIG_TIMEOUT = 60
+
def __init__(self, unique_id, children):
if children and children.count(None) > 0:
children = []
return highest + 1
@classmethod
- def _IsValidMeta(cls, meta_device):
- """Check if the given meta device looks like a valid one.
-
- """
- minor = cls._FindUnusedMinor()
- minor_path = cls._DevPath(minor)
- result = utils.RunCmd(["drbdmeta", minor_path,
- "v08", meta_device, "0",
- "dstate"])
- if result.failed:
- logging.error("Invalid meta device %s: %s", meta_device, result.output)
- return False
- return True
-
- @classmethod
def _GetShowParser(cls):
"""Return a parser for `drbd show` output.
def _AssembleLocal(cls, minor, backend, meta):
"""Configure the local part of a DRBD device.
- This is the first thing that must be done on an unconfigured DRBD
- device. And it must be done only once.
-
"""
- if not cls._IsValidMeta(meta):
- return False
args = ["drbdsetup", cls._DevPath(minor), "disk",
backend, meta, "0", "-e", "detach", "--create-device"]
result = utils.RunCmd(args)
# sure its shutdown
return cls._ShutdownNet(minor)
+ # Workaround for a race condition. When DRBD is doing its dance to
+ # establish a connection with its peer, it also sends the
+ # synchronization speed over the wire. In some cases setting the
+ # sync speed only after setting up both sides can race with DRBD
+ # connecting, hence we set it here before telling DRBD anything
+ # about its peer.
+ cls._SetMinorSyncSpeed(minor, constants.SYNC_SPEED)
+
args = ["drbdsetup", cls._DevPath(minor), "net",
"%s:%s" % (lhost, lport), "%s:%s" % (rhost, rport), protocol,
"-A", "discard-zero-changes",
if not self._CheckMetaSize(meta.dev_path):
raise errors.BlockDeviceError("Invalid meta device size")
self._InitMeta(self._FindUnusedMinor(), meta.dev_path)
- if not self._IsValidMeta(meta.dev_path):
- raise errors.BlockDeviceError("Cannot initalize meta device")
if not self._AssembleLocal(self.minor, backend.dev_path, meta.dev_path):
raise errors.BlockDeviceError("Can't attach to local storage")
raise errors.BlockDeviceError("Can't detach from local storage")
self._children = []
- def SetSyncSpeed(self, kbytes):
+ @classmethod
+ def _SetMinorSyncSpeed(cls, minor, kbytes):
"""Set the speed of the DRBD syncer.
+ This is the low-level implementation.
+
+ @type minor: int
+ @param minor: the drbd minor whose settings we change
+ @type kbytes: int
+ @param kbytes: the speed in kbytes/second
+ @rtype: boolean
+ @return: the success of the operation
+
"""
- children_result = super(DRBD8, self).SetSyncSpeed(kbytes)
- if self.minor is None:
- logging.info("Instance not attached to a device")
- return False
- result = utils.RunCmd(["drbdsetup", self.dev_path, "syncer", "-r", "%d" %
- kbytes])
+ result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "syncer",
+ "-r", "%d" % kbytes, "--create-device"])
if result.failed:
logging.error("Can't change syncer rate: %s - %s",
result.fail_reason, result.output)
- return not result.failed and children_result
+ return not result.failed
+
+ def SetSyncSpeed(self, kbytes):
+ """Set the speed of the DRBD syncer.
+
+ @type kbytes: int
+ @param kbytes: the speed in kbytes/second
+ @rtype: boolean
+ @return: the success of the operation
+
+ """
+ if self.minor is None:
+ logging.info("Not attached during SetSyncSpeed")
+ return False
+ children_result = super(DRBD8, self).SetSyncSpeed(kbytes)
+ return self._SetMinorSyncSpeed(self.minor, kbytes) and children_result
def GetProcStatus(self):
"""Return device data from /proc.
logging.error(msg)
raise errors.BlockDeviceError(msg)
+ def DisconnectNet(self):
+ """Removes network configuration.
+
+ This method shutdowns the network side of the device.
+
+ The method will wait up to a hardcoded timeout for the device to
+ go into standalone after the 'disconnect' command before
+ re-configuring it, as sometimes it takes a while for the
+ disconnect to actually propagate and thus we might issue a 'net'
+ command while the device is still connected. If the device will
+ still be attached to the network and we time out, we raise an
+ exception.
+
+ """
+ if self.minor is None:
+ raise errors.BlockDeviceError("DRBD disk not attached in re-attach net")
+
+ if None in (self._lhost, self._lport, self._rhost, self._rport):
+ raise errors.BlockDeviceError("DRBD disk missing network info in"
+ " DisconnectNet()")
+
+ ever_disconnected = self._ShutdownNet(self.minor)
+ timeout_limit = time.time() + self._NET_RECONFIG_TIMEOUT
+ sleep_time = 0.100 # we start the retry time at 100 miliseconds
+ while time.time() < timeout_limit:
+ status = self.GetProcStatus()
+ if status.is_standalone:
+ break
+ # retry the disconnect, it seems possible that due to a
+ # well-time disconnect on the peer, my disconnect command might
+ # be ingored and forgotten
+ ever_disconnected = self._ShutdownNet(self.minor) or ever_disconnected
+ time.sleep(sleep_time)
+ sleep_time = min(2, sleep_time * 1.5)
+
+ if not status.is_standalone:
+ if ever_disconnected:
+ msg = ("Device did not react to the"
+ " 'disconnect' command in a timely manner")
+ else:
+ msg = ("Can't shutdown network, even after multiple retries")
+ raise errors.BlockDeviceError(msg)
+
+ reconfig_time = time.time() - timeout_limit + self._NET_RECONFIG_TIMEOUT
+ if reconfig_time > 15: # hardcoded alert limit
+ logging.debug("DRBD8.DisconnectNet: detach took %.3f seconds",
+ reconfig_time)
+
+ def AttachNet(self, multimaster):
+ """Reconnects the network.
+
+ This method connects the network side of the device with a
+ specified multi-master flag. The device needs to be 'Standalone'
+ but have valid network configuration data.
+
+ Args:
+ - multimaster: init the network in dual-primary mode
+
+ """
+ if self.minor is None:
+ raise errors.BlockDeviceError("DRBD disk not attached in AttachNet")
+
+ if None in (self._lhost, self._lport, self._rhost, self._rport):
+ raise errors.BlockDeviceError("DRBD disk missing network info in"
+ " AttachNet()")
+
+ status = self.GetProcStatus()
+
+ if not status.is_standalone:
+ raise errors.BlockDeviceError("Device is not standalone in AttachNet")
+
+ return self._AssembleNet(self.minor,
+ (self._lhost, self._lport,
+ self._rhost, self._rport),
+ "C", dual_pri=multimaster)
+
def Attach(self):
- """Find a DRBD device which matches our config and attach to it.
+ """Check if our minor is configured.
+
+ This doesn't do any device configurations - it only checks if the
+ minor is in a state different from Unconfigured.
+
+ Note that this function will not change the state of the system in
+ any way (except in case of side-effects caused by reading from
+ /proc).
+
+ """
+ used_devs = self.GetUsedDevs()
+ if self._aminor in used_devs:
+ minor = self._aminor
+ else:
+ minor = None
+
+ self._SetFromMinor(minor)
+ return minor is not None
+
+ def Assemble(self):
+ """Assemble the drbd.
+
+ Method:
+ - if we have a configured device, we try to ensure that it matches
+ our config
+ - if not, we create it from zero
+
+ """
+ result = super(DRBD8, self).Assemble()
+ if not result:
+ return result
+
+ self.Attach()
+ if self.minor is None:
+ # local device completely unconfigured
+ return self._FastAssemble()
+ else:
+ # we have to recheck the local and network status and try to fix
+ # the device
+ return self._SlowAssemble()
+
+ def _SlowAssemble(self):
+ """Assembles the DRBD device from a (partially) configured device.
In case of partially attached (local device matches but no network
setup), we perform the network attach. If successful, we re-test
self._SetFromMinor(minor)
return minor is not None
- def Assemble(self):
- """Assemble the drbd.
+ def _FastAssemble(self):
+ """Assemble the drbd device from zero.
- Method:
- - if we have a local backing device, we bind to it by:
- - checking the list of used drbd devices
- - check if the local minor use of any of them is our own device
- - if yes, abort?
- - if not, bind
- - if we have a local/remote net info:
- - redo the local backing device step for the remote device
- - check if any drbd device is using the local port,
- if yes abort
- - check if any remote drbd device is using the remote
- port, if yes abort (for now)
- - bind our net port
- - bind the remote net port
+ This is run when in Assemble we detect our minor is unused.
"""
- self.Attach()
- if self.minor is not None:
- logging.info("Already assembled")
- return True
-
- result = super(DRBD8, self).Assemble()
- if not result:
- return result
-
# TODO: maybe completely tear-down the minor (drbdsetup ... down)
# before attaching our own?
minor = self._aminor
"""
if len(children) != 2:
raise errors.ProgrammerError("Invalid setup for the drbd device")
+ # check that the minor is unused
+ aminor = unique_id[4]
+ proc_info = cls._MassageProcData(cls._GetProcData())
+ if aminor in proc_info:
+ status = DRBD8Status(proc_info[aminor])
+ in_use = status.is_in_use
+ else:
+ in_use = False
+ if in_use:
+ raise errors.BlockDeviceError("DRBD minor %d already in use at"
+ " Create() time" % aminor)
meta = children[1]
meta.Assemble()
if not meta.Attach():
raise errors.BlockDeviceError("Can't attach to meta device")
if not cls._CheckMetaSize(meta.dev_path):
raise errors.BlockDeviceError("Invalid meta device size")
- cls._InitMeta(cls._FindUnusedMinor(), meta.dev_path)
- if not cls._IsValidMeta(meta.dev_path):
- raise errors.BlockDeviceError("Cannot initalize meta device")
+ cls._InitMeta(aminor, meta.dev_path)
return cls(unique_id, children)
def Grow(self, amount):
@return: an instance of FileStorage
"""
+ # TODO: decide whether we should check for existing files and
+ # abort or not
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2:
raise ValueError("Invalid configuration data %s" % str(unique_id))
dev_path = unique_id[1]
try:
f = open(dev_path, 'w')
- except IOError, err:
- raise errors.BlockDeviceError("Could not create '%'" % err)
- else:
f.truncate(size * 1024 * 1024)
f.close()
+ except IOError, err:
+ raise errors.BlockDeviceError("Error in file creation: %" % str(err))
return FileStorage(unique_id, children)
return device
-def AttachOrAssemble(dev_type, unique_id, children):
+def Assemble(dev_type, unique_id, children):
"""Try to attach or assemble an existing device.
- This will attach to an existing assembled device or will assemble
- the device, as needed, to bring it fully up.
+ This will attach to assemble the device, as needed, to bring it
+ fully up. It must be safe to run on already-assembled devices.
"""
if dev_type not in DEV_MAP:
raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type)
device = DEV_MAP[dev_type](unique_id, children)
- if not device.attached:
- device.Assemble()
- if not device.attached:
- raise errors.BlockDeviceError("Can't find a valid block device for"
- " %s/%s/%s" %
- (dev_type, unique_id, children))
+ if not device.Assemble():
+ raise errors.BlockDeviceError("Can't find a valid block device for"
+ " %s/%s/%s" %
+ (dev_type, unique_id, children))
return device
projects / ganeti-local / blobdiff