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# Copyright (C) 2006, 2007 Google Inc.
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful, but
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# WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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# General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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# 02110-1301, USA.
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"""Block device abstraction"""
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import re |
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import time |
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import errno |
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import pyparsing as pyp |
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import os |
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from ganeti import utils |
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from ganeti import logger |
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from ganeti import errors |
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from ganeti import constants |
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class BlockDev(object): |
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"""Block device abstract class.
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A block device can be in the following states:
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- not existing on the system, and by `Create()` it goes into:
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- existing but not setup/not active, and by `Assemble()` goes into:
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- active read-write and by `Open()` it goes into
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- online (=used, or ready for use)
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A device can also be online but read-only, however we are not using
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the readonly state (MD and LV have it, if needed in the future)
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and we are usually looking at this like at a stack, so it's easier
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to conceptualise the transition from not-existing to online and back
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like a linear one.
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The many different states of the device are due to the fact that we
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need to cover many device types:
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- logical volumes are created, lvchange -a y $lv, and used
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- md arrays are created or assembled and used
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- drbd devices are attached to a local disk/remote peer and made primary
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A block device is identified by three items:
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- the /dev path of the device (dynamic)
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- a unique ID of the device (static)
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- it's major/minor pair (dynamic)
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Not all devices implement both the first two as distinct items. LVM
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logical volumes have their unique ID (the pair volume group, logical
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volume name) in a 1-to-1 relation to the dev path. For MD devices,
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the /dev path is dynamic and the unique ID is the UUID generated at
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array creation plus the slave list. For DRBD devices, the /dev path
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is again dynamic and the unique id is the pair (host1, dev1),
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(host2, dev2).
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You can get to a device in two ways:
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- creating the (real) device, which returns you
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an attached instance (lvcreate, mdadm --create)
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- attaching of a python instance to an existing (real) device
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The second point, the attachement to a device, is different
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depending on whether the device is assembled or not. At init() time,
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we search for a device with the same unique_id as us. If found,
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good. It also means that the device is already assembled. If not,
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after assembly we'll have our correct major/minor.
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"""
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def __init__(self, unique_id, children): |
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self._children = children
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self.dev_path = None |
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self.unique_id = unique_id
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self.major = None |
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self.minor = None |
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def Assemble(self): |
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"""Assemble the device from its components.
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If this is a plain block device (e.g. LVM) than assemble does
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nothing, as the LVM has no children and we don't put logical
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volumes offline.
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One guarantee is that after the device has been assembled, it
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knows its major/minor numbers. This allows other devices (usually
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parents) to probe correctly for their children.
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"""
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status = True
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for child in self._children: |
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if not isinstance(child, BlockDev): |
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raise TypeError("Invalid child passed of type '%s'" % type(child)) |
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if not status: |
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break
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status = status and child.Assemble()
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if not status: |
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break
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try:
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child.Open() |
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except errors.BlockDeviceError:
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for child in self._children: |
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child.Shutdown() |
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raise
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if not status: |
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for child in self._children: |
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child.Shutdown() |
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return status
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def Attach(self): |
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"""Find a device which matches our config and attach to it.
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"""
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raise NotImplementedError |
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def Close(self): |
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"""Notifies that the device will no longer be used for I/O.
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"""
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raise NotImplementedError |
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@classmethod
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def Create(cls, unique_id, children, size): |
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"""Create the device.
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If the device cannot be created, it will return None
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instead. Error messages go to the logging system.
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Note that for some devices, the unique_id is used, and for other,
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the children. The idea is that these two, taken together, are
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enough for both creation and assembly (later).
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"""
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raise NotImplementedError |
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def Remove(self): |
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"""Remove this device.
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This makes sense only for some of the device types: LV and to a
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lesser degree, md devices. Also note that if the device can't
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attach, the removal can't be completed.
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"""
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raise NotImplementedError |
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def Rename(self, new_id): |
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"""Rename this device.
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This may or may not make sense for a given device type.
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"""
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raise NotImplementedError |
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def Open(self, force=False): |
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"""Make the device ready for use.
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This makes the device ready for I/O. For now, just the DRBD
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devices need this.
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The force parameter signifies that if the device has any kind of
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--force thing, it should be used, we know what we are doing.
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"""
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raise NotImplementedError |
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def Shutdown(self): |
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"""Shut down the device, freeing its children.
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This undoes the `Assemble()` work, except for the child
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assembling; as such, the children on the device are still
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assembled after this call.
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"""
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raise NotImplementedError |
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def SetSyncSpeed(self, speed): |
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"""Adjust the sync speed of the mirror.
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In case this is not a mirroring device, this is no-op.
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"""
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result = True
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if self._children: |
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for child in self._children: |
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result = result and child.SetSyncSpeed(speed)
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return result
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def GetSyncStatus(self): |
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"""Returns the sync status of the device.
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If this device is a mirroring device, this function returns the
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status of the mirror.
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Returns:
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(sync_percent, estimated_time, is_degraded, ldisk)
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If sync_percent is None, it means the device is not syncing.
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If estimated_time is None, it means we can't estimate
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the time needed, otherwise it's the time left in seconds.
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If is_degraded is True, it means the device is missing
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redundancy. This is usually a sign that something went wrong in
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the device setup, if sync_percent is None.
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The ldisk parameter represents the degradation of the local
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data. This is only valid for some devices, the rest will always
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return False (not degraded).
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"""
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return None, None, False, False |
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def CombinedSyncStatus(self): |
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"""Calculate the mirror status recursively for our children.
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The return value is the same as for `GetSyncStatus()` except the
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minimum percent and maximum time are calculated across our
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children.
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"""
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min_percent, max_time, is_degraded, ldisk = self.GetSyncStatus()
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if self._children: |
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for child in self._children: |
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c_percent, c_time, c_degraded, c_ldisk = child.GetSyncStatus() |
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if min_percent is None: |
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min_percent = c_percent |
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elif c_percent is not None: |
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min_percent = min(min_percent, c_percent)
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if max_time is None: |
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max_time = c_time |
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elif c_time is not None: |
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max_time = max(max_time, c_time)
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is_degraded = is_degraded or c_degraded
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ldisk = ldisk or c_ldisk
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return min_percent, max_time, is_degraded, ldisk
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def SetInfo(self, text): |
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"""Update metadata with info text.
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Only supported for some device types.
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"""
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for child in self._children: |
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child.SetInfo(text) |
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def __repr__(self): |
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return ("<%s: unique_id: %s, children: %s, %s:%s, %s>" % |
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(self.__class__, self.unique_id, self._children, |
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self.major, self.minor, self.dev_path)) |
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class LogicalVolume(BlockDev): |
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"""Logical Volume block device.
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"""
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def __init__(self, unique_id, children): |
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"""Attaches to a LV device.
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The unique_id is a tuple (vg_name, lv_name)
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"""
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super(LogicalVolume, self).__init__(unique_id, children) |
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if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2: |
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raise ValueError("Invalid configuration data %s" % str(unique_id)) |
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self._vg_name, self._lv_name = unique_id |
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self.dev_path = "/dev/%s/%s" % (self._vg_name, self._lv_name) |
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self.Attach()
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@classmethod
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def Create(cls, unique_id, children, size): |
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"""Create a new logical volume.
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"""
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if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2: |
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raise ValueError("Invalid configuration data %s" % str(unique_id)) |
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vg_name, lv_name = unique_id |
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pvs_info = cls.GetPVInfo(vg_name) |
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if not pvs_info: |
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raise errors.BlockDeviceError("Can't compute PV info for vg %s" % |
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vg_name) |
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pvs_info.sort() |
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pvs_info.reverse() |
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pvlist = [ pv[1] for pv in pvs_info ] |
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free_size = sum([ pv[0] for pv in pvs_info ]) |
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# The size constraint should have been checked from the master before
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# calling the create function.
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if free_size < size:
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raise errors.BlockDeviceError("Not enough free space: required %s," |
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" available %s" % (size, free_size))
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result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-n%s" % lv_name, |
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vg_name] + pvlist) |
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if result.failed:
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raise errors.BlockDeviceError(result.fail_reason)
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return LogicalVolume(unique_id, children)
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@staticmethod
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def GetPVInfo(vg_name): |
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"""Get the free space info for PVs in a volume group.
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Args:
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vg_name: the volume group name
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Returns:
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list of (free_space, name) with free_space in mebibytes
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"""
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command = ["pvs", "--noheadings", "--nosuffix", "--units=m", |
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"-opv_name,vg_name,pv_free,pv_attr", "--unbuffered", |
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"--separator=:"]
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result = utils.RunCmd(command) |
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if result.failed:
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logger.Error("Can't get the PV information: %s" % result.fail_reason)
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return None |
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data = [] |
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for line in result.stdout.splitlines(): |
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fields = line.strip().split(':')
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if len(fields) != 4: |
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logger.Error("Can't parse pvs output: line '%s'" % line)
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return None |
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# skip over pvs from another vg or ones which are not allocatable
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if fields[1] != vg_name or fields[3][0] != 'a': |
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continue
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data.append((float(fields[2]), fields[0])) |
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return data
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def Remove(self): |
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"""Remove this logical volume.
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"""
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if not self.minor and not self.Attach(): |
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# the LV does not exist
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return True |
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result = utils.RunCmd(["lvremove", "-f", "%s/%s" % |
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(self._vg_name, self._lv_name)]) |
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if result.failed:
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logger.Error("Can't lvremove: %s" % result.fail_reason)
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return not result.failed |
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def Rename(self, new_id): |
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"""Rename this logical volume.
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"""
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if not isinstance(new_id, (tuple, list)) or len(new_id) != 2: |
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raise errors.ProgrammerError("Invalid new logical id '%s'" % new_id) |
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new_vg, new_name = new_id |
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if new_vg != self._vg_name: |
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raise errors.ProgrammerError("Can't move a logical volume across" |
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" volume groups (from %s to to %s)" %
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(self._vg_name, new_vg))
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result = utils.RunCmd(["lvrename", new_vg, self._lv_name, new_name]) |
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if result.failed:
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raise errors.BlockDeviceError("Failed to rename the logical volume: %s" % |
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result.output) |
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self._lv_name = new_name
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self.dev_path = "/dev/%s/%s" % (self._vg_name, self._lv_name) |
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def Attach(self): |
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"""Attach to an existing LV.
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This method will try to see if an existing and active LV exists
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which matches our name. If so, its major/minor will be
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recorded.
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"""
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result = utils.RunCmd(["lvdisplay", self.dev_path]) |
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if result.failed:
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logger.Error("Can't find LV %s: %s, %s" %
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(self.dev_path, result.fail_reason, result.output))
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return False |
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match = re.compile("^ *Block device *([0-9]+):([0-9]+).*$")
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for line in result.stdout.splitlines(): |
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match_result = match.match(line) |
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if match_result:
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self.major = int(match_result.group(1)) |
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self.minor = int(match_result.group(2)) |
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return True |
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return False |
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def Assemble(self): |
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"""Assemble the device.
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We alway run `lvchange -ay` on the LV to ensure it's active before
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use, as there were cases when xenvg was not active after boot
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(also possibly after disk issues).
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"""
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result = utils.RunCmd(["lvchange", "-ay", self.dev_path]) |
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if result.failed:
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logger.Error("Can't activate lv %s: %s" % (self.dev_path, result.output)) |
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return not result.failed |
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def Shutdown(self): |
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"""Shutdown the device.
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This is a no-op for the LV device type, as we don't deactivate the
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volumes on shutdown.
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"""
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return True |
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def GetSyncStatus(self): |
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"""Returns the sync status of the device.
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If this device is a mirroring device, this function returns the
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status of the mirror.
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Returns:
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(sync_percent, estimated_time, is_degraded, ldisk)
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For logical volumes, sync_percent and estimated_time are always
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None (no recovery in progress, as we don't handle the mirrored LV
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case). The is_degraded parameter is the inverse of the ldisk
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parameter.
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For the ldisk parameter, we check if the logical volume has the
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'virtual' type, which means it's not backed by existing storage
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anymore (read from it return I/O error). This happens after a
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physical disk failure and subsequent 'vgreduce --removemissing' on
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the volume group.
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"""
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result = utils.RunCmd(["lvs", "--noheadings", "-olv_attr", self.dev_path]) |
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if result.failed:
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logger.Error("Can't display lv: %s" % result.fail_reason)
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return None, None, True, True |
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out = result.stdout.strip() |
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# format: type/permissions/alloc/fixed_minor/state/open
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if len(out) != 6: |
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logger.Debug("Error in lvs output: attrs=%s, len != 6" % out)
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return None, None, True, True |
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ldisk = out[0] == 'v' # virtual volume, i.e. doesn't have |
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# backing storage
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return None, None, ldisk, ldisk |
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def Open(self, force=False): |
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"""Make the device ready for I/O.
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This is a no-op for the LV device type.
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"""
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pass
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def Close(self): |
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"""Notifies that the device will no longer be used for I/O.
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This is a no-op for the LV device type.
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"""
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pass
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def Snapshot(self, size): |
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"""Create a snapshot copy of an lvm block device.
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"""
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snap_name = self._lv_name + ".snap" |
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# remove existing snapshot if found
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snap = LogicalVolume((self._vg_name, snap_name), None) |
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snap.Remove() |
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pvs_info = self.GetPVInfo(self._vg_name) |
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if not pvs_info: |
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raise errors.BlockDeviceError("Can't compute PV info for vg %s" % |
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self._vg_name)
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pvs_info.sort() |
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pvs_info.reverse() |
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free_size, pv_name = pvs_info[0]
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if free_size < size:
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raise errors.BlockDeviceError("Not enough free space: required %s," |
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" available %s" % (size, free_size))
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result = utils.RunCmd(["lvcreate", "-L%dm" % size, "-s", |
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"-n%s" % snap_name, self.dev_path]) |
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if result.failed:
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raise errors.BlockDeviceError("command: %s error: %s" % |
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(result.cmd, result.fail_reason)) |
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return snap_name
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def SetInfo(self, text): |
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"""Update metadata with info text.
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"""
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BlockDev.SetInfo(self, text)
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|
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# Replace invalid characters
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text = re.sub('^[^A-Za-z0-9_+.]', '_', text) |
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text = re.sub('[^-A-Za-z0-9_+.]', '_', text) |
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# Only up to 128 characters are allowed
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text = text[:128]
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|
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result = utils.RunCmd(["lvchange", "--addtag", text, |
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self.dev_path])
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if result.failed:
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raise errors.BlockDeviceError("Command: %s error: %s" % |
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(result.cmd, result.fail_reason)) |
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|
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|
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class MDRaid1(BlockDev): |
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"""raid1 device implemented via md.
|
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|
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"""
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524 |
def __init__(self, unique_id, children): |
525 |
super(MDRaid1, self).__init__(unique_id, children) |
526 |
self.major = 9 |
527 |
self.Attach()
|
528 |
|
529 |
def Attach(self): |
530 |
"""Find an array which matches our config and attach to it.
|
531 |
|
532 |
This tries to find a MD array which has the same UUID as our own.
|
533 |
|
534 |
"""
|
535 |
minor = self._FindMDByUUID(self.unique_id) |
536 |
if minor is not None: |
537 |
self._SetFromMinor(minor)
|
538 |
else:
|
539 |
self.minor = None |
540 |
self.dev_path = None |
541 |
|
542 |
return (minor is not None) |
543 |
|
544 |
@staticmethod
|
545 |
def _GetUsedDevs(): |
546 |
"""Compute the list of in-use MD devices.
|
547 |
|
548 |
It doesn't matter if the used device have other raid level, just
|
549 |
that they are in use.
|
550 |
|
551 |
"""
|
552 |
mdstat = open("/proc/mdstat", "r") |
553 |
data = mdstat.readlines() |
554 |
mdstat.close() |
555 |
|
556 |
used_md = {} |
557 |
valid_line = re.compile("^md([0-9]+) : .*$")
|
558 |
for line in data: |
559 |
match = valid_line.match(line) |
560 |
if match:
|
561 |
md_no = int(match.group(1)) |
562 |
used_md[md_no] = line |
563 |
|
564 |
return used_md
|
565 |
|
566 |
@staticmethod
|
567 |
def _GetDevInfo(minor): |
568 |
"""Get info about a MD device.
|
569 |
|
570 |
Currently only uuid is returned.
|
571 |
|
572 |
"""
|
573 |
result = utils.RunCmd(["mdadm", "-D", "/dev/md%d" % minor]) |
574 |
if result.failed:
|
575 |
logger.Error("Can't display md: %s" % result.fail_reason)
|
576 |
return None |
577 |
retval = {} |
578 |
for line in result.stdout.splitlines(): |
579 |
line = line.strip() |
580 |
kv = line.split(" : ", 1) |
581 |
if kv:
|
582 |
if kv[0] == "UUID": |
583 |
retval["uuid"] = kv[1].split()[0] |
584 |
elif kv[0] == "State": |
585 |
retval["state"] = kv[1].split(", ") |
586 |
return retval
|
587 |
|
588 |
@staticmethod
|
589 |
def _FindUnusedMinor(): |
590 |
"""Compute an unused MD minor.
|
591 |
|
592 |
This code assumes that there are 256 minors only.
|
593 |
|
594 |
"""
|
595 |
used_md = MDRaid1._GetUsedDevs() |
596 |
i = 0
|
597 |
while i < 256: |
598 |
if i not in used_md: |
599 |
break
|
600 |
i += 1
|
601 |
if i == 256: |
602 |
logger.Error("Critical: Out of md minor numbers.")
|
603 |
raise errors.BlockDeviceError("Can't find a free MD minor") |
604 |
return i
|
605 |
|
606 |
@classmethod
|
607 |
def _FindMDByUUID(cls, uuid): |
608 |
"""Find the minor of an MD array with a given UUID.
|
609 |
|
610 |
"""
|
611 |
md_list = cls._GetUsedDevs() |
612 |
for minor in md_list: |
613 |
info = cls._GetDevInfo(minor) |
614 |
if info and info["uuid"] == uuid: |
615 |
return minor
|
616 |
return None |
617 |
|
618 |
@staticmethod
|
619 |
def _ZeroSuperblock(dev_path): |
620 |
"""Zero the possible locations for an MD superblock.
|
621 |
|
622 |
The zero-ing can't be done via ``mdadm --zero-superblock`` as that
|
623 |
fails in versions 2.x with the same error code as non-writable
|
624 |
device.
|
625 |
|
626 |
The superblocks are located at (negative values are relative to
|
627 |
the end of the block device):
|
628 |
- -128k to end for version 0.90 superblock
|
629 |
- -8k to -12k for version 1.0 superblock (included in the above)
|
630 |
- 0k to 4k for version 1.1 superblock
|
631 |
- 4k to 8k for version 1.2 superblock
|
632 |
|
633 |
To cover all situations, the zero-ing will be:
|
634 |
- 0k to 128k
|
635 |
- -128k to end
|
636 |
|
637 |
As such, the minimum device size must be 128k, otherwise we'll get
|
638 |
I/O errors.
|
639 |
|
640 |
Note that this function depends on the fact that one can open,
|
641 |
read and write block devices normally.
|
642 |
|
643 |
"""
|
644 |
overwrite_size = 128 * 1024 |
645 |
empty_buf = '\0' * overwrite_size
|
646 |
fd = open(dev_path, "r+") |
647 |
try:
|
648 |
fd.seek(0, 0) |
649 |
p1 = fd.tell() |
650 |
fd.write(empty_buf) |
651 |
p2 = fd.tell() |
652 |
logger.Debug("Zeroed %s from %d to %d" % (dev_path, p1, p2))
|
653 |
fd.seek(-overwrite_size, 2)
|
654 |
p1 = fd.tell() |
655 |
fd.write(empty_buf) |
656 |
p2 = fd.tell() |
657 |
logger.Debug("Zeroed %s from %d to %d" % (dev_path, p1, p2))
|
658 |
finally:
|
659 |
fd.close() |
660 |
|
661 |
@classmethod
|
662 |
def Create(cls, unique_id, children, size): |
663 |
"""Create a new MD raid1 array.
|
664 |
|
665 |
"""
|
666 |
if not isinstance(children, (tuple, list)): |
667 |
raise ValueError("Invalid setup data for MDRaid1 dev: %s" % |
668 |
str(children))
|
669 |
for i in children: |
670 |
if not isinstance(i, BlockDev): |
671 |
raise ValueError("Invalid member in MDRaid1 dev: %s" % type(i)) |
672 |
for i in children: |
673 |
try:
|
674 |
cls._ZeroSuperblock(i.dev_path) |
675 |
except EnvironmentError, err: |
676 |
logger.Error("Can't zero superblock for %s: %s" %
|
677 |
(i.dev_path, str(err)))
|
678 |
return None |
679 |
minor = cls._FindUnusedMinor() |
680 |
result = utils.RunCmd(["mdadm", "--create", "/dev/md%d" % minor, |
681 |
"--auto=yes", "--force", "-l1", |
682 |
"-n%d" % len(children)] + |
683 |
[dev.dev_path for dev in children]) |
684 |
|
685 |
if result.failed:
|
686 |
logger.Error("Can't create md: %s: %s" % (result.fail_reason,
|
687 |
result.output)) |
688 |
return None |
689 |
info = cls._GetDevInfo(minor) |
690 |
if not info or not "uuid" in info: |
691 |
logger.Error("Wrong information returned from mdadm -D: %s" % str(info)) |
692 |
return None |
693 |
return MDRaid1(info["uuid"], children) |
694 |
|
695 |
def Remove(self): |
696 |
"""Stub remove function for MD RAID 1 arrays.
|
697 |
|
698 |
We don't remove the superblock right now. Mark a to do.
|
699 |
|
700 |
"""
|
701 |
#TODO: maybe zero superblock on child devices?
|
702 |
return self.Shutdown() |
703 |
|
704 |
def Rename(self, new_id): |
705 |
"""Rename a device.
|
706 |
|
707 |
This is not supported for md raid1 devices.
|
708 |
|
709 |
"""
|
710 |
raise errors.ProgrammerError("Can't rename a md raid1 device") |
711 |
|
712 |
def AddChildren(self, devices): |
713 |
"""Add new member(s) to the md raid1.
|
714 |
|
715 |
"""
|
716 |
if self.minor is None and not self.Attach(): |
717 |
raise errors.BlockDeviceError("Can't attach to device") |
718 |
|
719 |
args = ["mdadm", "-a", self.dev_path] |
720 |
for dev in devices: |
721 |
if dev.dev_path is None: |
722 |
raise errors.BlockDeviceError("Child '%s' is not initialised" % dev) |
723 |
dev.Open() |
724 |
args.append(dev.dev_path) |
725 |
result = utils.RunCmd(args) |
726 |
if result.failed:
|
727 |
raise errors.BlockDeviceError("Failed to add new device to array: %s" % |
728 |
result.output) |
729 |
new_len = len(self._children) + len(devices) |
730 |
result = utils.RunCmd(["mdadm", "--grow", self.dev_path, "-n", new_len]) |
731 |
if result.failed:
|
732 |
raise errors.BlockDeviceError("Can't grow md array: %s" % |
733 |
result.output) |
734 |
self._children.extend(devices)
|
735 |
|
736 |
def RemoveChildren(self, devices): |
737 |
"""Remove member(s) from the md raid1.
|
738 |
|
739 |
"""
|
740 |
if self.minor is None and not self.Attach(): |
741 |
raise errors.BlockDeviceError("Can't attach to device") |
742 |
new_len = len(self._children) - len(devices) |
743 |
if new_len < 1: |
744 |
raise errors.BlockDeviceError("Can't reduce to less than one child") |
745 |
args = ["mdadm", "-f", self.dev_path] |
746 |
orig_devs = [] |
747 |
for dev in devices: |
748 |
args.append(dev) |
749 |
for c in self._children: |
750 |
if c.dev_path == dev:
|
751 |
orig_devs.append(c) |
752 |
break
|
753 |
else:
|
754 |
raise errors.BlockDeviceError("Can't find device '%s' for removal" % |
755 |
dev) |
756 |
result = utils.RunCmd(args) |
757 |
if result.failed:
|
758 |
raise errors.BlockDeviceError("Failed to mark device(s) as failed: %s" % |
759 |
result.output) |
760 |
|
761 |
# it seems here we need a short delay for MD to update its
|
762 |
# superblocks
|
763 |
time.sleep(0.5)
|
764 |
args[1] = "-r" |
765 |
result = utils.RunCmd(args) |
766 |
if result.failed:
|
767 |
raise errors.BlockDeviceError("Failed to remove device(s) from array:" |
768 |
" %s" % result.output)
|
769 |
result = utils.RunCmd(["mdadm", "--grow", "--force", self.dev_path, |
770 |
"-n", new_len])
|
771 |
if result.failed:
|
772 |
raise errors.BlockDeviceError("Can't shrink md array: %s" % |
773 |
result.output) |
774 |
for dev in orig_devs: |
775 |
self._children.remove(dev)
|
776 |
|
777 |
def _SetFromMinor(self, minor): |
778 |
"""Set our parameters based on the given minor.
|
779 |
|
780 |
This sets our minor variable and our dev_path.
|
781 |
|
782 |
"""
|
783 |
self.minor = minor
|
784 |
self.dev_path = "/dev/md%d" % minor |
785 |
|
786 |
def Assemble(self): |
787 |
"""Assemble the MD device.
|
788 |
|
789 |
At this point we should have:
|
790 |
- list of children devices
|
791 |
- uuid
|
792 |
|
793 |
"""
|
794 |
result = super(MDRaid1, self).Assemble() |
795 |
if not result: |
796 |
return result
|
797 |
md_list = self._GetUsedDevs()
|
798 |
for minor in md_list: |
799 |
info = self._GetDevInfo(minor)
|
800 |
if info and info["uuid"] == self.unique_id: |
801 |
self._SetFromMinor(minor)
|
802 |
logger.Info("MD array %s already started" % str(self)) |
803 |
return True |
804 |
free_minor = self._FindUnusedMinor()
|
805 |
result = utils.RunCmd(["mdadm", "-A", "--auto=yes", "--uuid", |
806 |
self.unique_id, "/dev/md%d" % free_minor] + |
807 |
[bdev.dev_path for bdev in self._children]) |
808 |
if result.failed:
|
809 |
logger.Error("Can't assemble MD array: %s: %s" %
|
810 |
(result.fail_reason, result.output)) |
811 |
self.minor = None |
812 |
else:
|
813 |
self.minor = free_minor
|
814 |
return not result.failed |
815 |
|
816 |
def Shutdown(self): |
817 |
"""Tear down the MD array.
|
818 |
|
819 |
This does a 'mdadm --stop' so after this command, the array is no
|
820 |
longer available.
|
821 |
|
822 |
"""
|
823 |
if self.minor is None and not self.Attach(): |
824 |
logger.Info("MD object not attached to a device")
|
825 |
return True |
826 |
|
827 |
result = utils.RunCmd(["mdadm", "--stop", "/dev/md%d" % self.minor]) |
828 |
if result.failed:
|
829 |
logger.Error("Can't stop MD array: %s" % result.fail_reason)
|
830 |
return False |
831 |
self.minor = None |
832 |
self.dev_path = None |
833 |
return True |
834 |
|
835 |
def SetSyncSpeed(self, kbytes): |
836 |
"""Set the maximum sync speed for the MD array.
|
837 |
|
838 |
"""
|
839 |
result = super(MDRaid1, self).SetSyncSpeed(kbytes) |
840 |
if self.minor is None: |
841 |
logger.Error("MD array not attached to a device")
|
842 |
return False |
843 |
f = open("/sys/block/md%d/md/sync_speed_max" % self.minor, "w") |
844 |
try:
|
845 |
f.write("%d" % kbytes)
|
846 |
finally:
|
847 |
f.close() |
848 |
f = open("/sys/block/md%d/md/sync_speed_min" % self.minor, "w") |
849 |
try:
|
850 |
f.write("%d" % (kbytes/2)) |
851 |
finally:
|
852 |
f.close() |
853 |
return result
|
854 |
|
855 |
def GetSyncStatus(self): |
856 |
"""Returns the sync status of the device.
|
857 |
|
858 |
Returns:
|
859 |
(sync_percent, estimated_time, is_degraded, ldisk)
|
860 |
|
861 |
If sync_percent is None, it means all is ok
|
862 |
If estimated_time is None, it means we can't esimate
|
863 |
the time needed, otherwise it's the time left in seconds.
|
864 |
|
865 |
The ldisk parameter is always true for MD devices.
|
866 |
|
867 |
"""
|
868 |
if self.minor is None and not self.Attach(): |
869 |
raise errors.BlockDeviceError("Can't attach to device in GetSyncStatus") |
870 |
dev_info = self._GetDevInfo(self.minor) |
871 |
is_clean = ("state" in dev_info and |
872 |
len(dev_info["state"]) == 1 and |
873 |
dev_info["state"][0] in ("clean", "active")) |
874 |
sys_path = "/sys/block/md%s/md/" % self.minor |
875 |
f = file(sys_path + "sync_action") |
876 |
sync_status = f.readline().strip() |
877 |
f.close() |
878 |
if sync_status == "idle": |
879 |
return None, None, not is_clean, False |
880 |
f = file(sys_path + "sync_completed") |
881 |
sync_completed = f.readline().strip().split(" / ")
|
882 |
f.close() |
883 |
if len(sync_completed) != 2: |
884 |
return 0, None, not is_clean, False |
885 |
sync_done, sync_total = [float(i) for i in sync_completed] |
886 |
sync_percent = 100.0*sync_done/sync_total
|
887 |
f = file(sys_path + "sync_speed") |
888 |
sync_speed_k = int(f.readline().strip())
|
889 |
if sync_speed_k == 0: |
890 |
time_est = None
|
891 |
else:
|
892 |
time_est = (sync_total - sync_done) / 2 / sync_speed_k
|
893 |
return sync_percent, time_est, not is_clean, False |
894 |
|
895 |
def Open(self, force=False): |
896 |
"""Make the device ready for I/O.
|
897 |
|
898 |
This is a no-op for the MDRaid1 device type, although we could use
|
899 |
the 2.6.18's new array_state thing.
|
900 |
|
901 |
"""
|
902 |
pass
|
903 |
|
904 |
def Close(self): |
905 |
"""Notifies that the device will no longer be used for I/O.
|
906 |
|
907 |
This is a no-op for the MDRaid1 device type, but see comment for
|
908 |
`Open()`.
|
909 |
|
910 |
"""
|
911 |
pass
|
912 |
|
913 |
|
914 |
class BaseDRBD(BlockDev): |
915 |
"""Base DRBD class.
|
916 |
|
917 |
This class contains a few bits of common functionality between the
|
918 |
0.7 and 8.x versions of DRBD.
|
919 |
|
920 |
"""
|
921 |
_VERSION_RE = re.compile(r"^version: (\d+)\.(\d+)\.(\d+)"
|
922 |
r" \(api:(\d+)/proto:(\d+)(?:-(\d+))?\)")
|
923 |
|
924 |
_DRBD_MAJOR = 147
|
925 |
_ST_UNCONFIGURED = "Unconfigured"
|
926 |
_ST_WFCONNECTION = "WFConnection"
|
927 |
_ST_CONNECTED = "Connected"
|
928 |
|
929 |
@staticmethod
|
930 |
def _GetProcData(): |
931 |
"""Return data from /proc/drbd.
|
932 |
|
933 |
"""
|
934 |
stat = open("/proc/drbd", "r") |
935 |
try:
|
936 |
data = stat.read().splitlines() |
937 |
finally:
|
938 |
stat.close() |
939 |
if not data: |
940 |
raise errors.BlockDeviceError("Can't read any data from /proc/drbd") |
941 |
return data
|
942 |
|
943 |
@staticmethod
|
944 |
def _MassageProcData(data): |
945 |
"""Transform the output of _GetProdData into a nicer form.
|
946 |
|
947 |
Returns:
|
948 |
a dictionary of minor: joined lines from /proc/drbd for that minor
|
949 |
|
950 |
"""
|
951 |
lmatch = re.compile("^ *([0-9]+):.*$")
|
952 |
results = {} |
953 |
old_minor = old_line = None
|
954 |
for line in data: |
955 |
lresult = lmatch.match(line) |
956 |
if lresult is not None: |
957 |
if old_minor is not None: |
958 |
results[old_minor] = old_line |
959 |
old_minor = int(lresult.group(1)) |
960 |
old_line = line |
961 |
else:
|
962 |
if old_minor is not None: |
963 |
old_line += " " + line.strip()
|
964 |
# add last line
|
965 |
if old_minor is not None: |
966 |
results[old_minor] = old_line |
967 |
return results
|
968 |
|
969 |
@classmethod
|
970 |
def _GetVersion(cls): |
971 |
"""Return the DRBD version.
|
972 |
|
973 |
This will return a dict with keys:
|
974 |
k_major,
|
975 |
k_minor,
|
976 |
k_point,
|
977 |
api,
|
978 |
proto,
|
979 |
proto2 (only on drbd > 8.2.X)
|
980 |
|
981 |
"""
|
982 |
proc_data = cls._GetProcData() |
983 |
first_line = proc_data[0].strip()
|
984 |
version = cls._VERSION_RE.match(first_line) |
985 |
if not version: |
986 |
raise errors.BlockDeviceError("Can't parse DRBD version from '%s'" % |
987 |
first_line) |
988 |
|
989 |
values = version.groups() |
990 |
retval = {'k_major': int(values[0]), |
991 |
'k_minor': int(values[1]), |
992 |
'k_point': int(values[2]), |
993 |
'api': int(values[3]), |
994 |
'proto': int(values[4]), |
995 |
} |
996 |
if values[5] is not None: |
997 |
retval['proto2'] = values[5] |
998 |
|
999 |
return retval
|
1000 |
|
1001 |
@staticmethod
|
1002 |
def _DevPath(minor): |
1003 |
"""Return the path to a drbd device for a given minor.
|
1004 |
|
1005 |
"""
|
1006 |
return "/dev/drbd%d" % minor |
1007 |
|
1008 |
@classmethod
|
1009 |
def _GetUsedDevs(cls): |
1010 |
"""Compute the list of used DRBD devices.
|
1011 |
|
1012 |
"""
|
1013 |
data = cls._GetProcData() |
1014 |
|
1015 |
used_devs = {} |
1016 |
valid_line = re.compile("^ *([0-9]+): cs:([^ ]+).*$")
|
1017 |
for line in data: |
1018 |
match = valid_line.match(line) |
1019 |
if not match: |
1020 |
continue
|
1021 |
minor = int(match.group(1)) |
1022 |
state = match.group(2)
|
1023 |
if state == cls._ST_UNCONFIGURED:
|
1024 |
continue
|
1025 |
used_devs[minor] = state, line |
1026 |
|
1027 |
return used_devs
|
1028 |
|
1029 |
def _SetFromMinor(self, minor): |
1030 |
"""Set our parameters based on the given minor.
|
1031 |
|
1032 |
This sets our minor variable and our dev_path.
|
1033 |
|
1034 |
"""
|
1035 |
if minor is None: |
1036 |
self.minor = self.dev_path = None |
1037 |
else:
|
1038 |
self.minor = minor
|
1039 |
self.dev_path = self._DevPath(minor) |
1040 |
|
1041 |
@staticmethod
|
1042 |
def _CheckMetaSize(meta_device): |
1043 |
"""Check if the given meta device looks like a valid one.
|
1044 |
|
1045 |
This currently only check the size, which must be around
|
1046 |
128MiB.
|
1047 |
|
1048 |
"""
|
1049 |
result = utils.RunCmd(["blockdev", "--getsize", meta_device]) |
1050 |
if result.failed:
|
1051 |
logger.Error("Failed to get device size: %s" % result.fail_reason)
|
1052 |
return False |
1053 |
try:
|
1054 |
sectors = int(result.stdout)
|
1055 |
except ValueError: |
1056 |
logger.Error("Invalid output from blockdev: '%s'" % result.stdout)
|
1057 |
return False |
1058 |
bytes = sectors * 512
|
1059 |
if bytes < 128 * 1024 * 1024: # less than 128MiB |
1060 |
logger.Error("Meta device too small (%.2fMib)" % (bytes / 1024 / 1024)) |
1061 |
return False |
1062 |
if bytes > (128 + 32) * 1024 * 1024: # account for an extra (big) PE on LVM |
1063 |
logger.Error("Meta device too big (%.2fMiB)" % (bytes / 1024 / 1024)) |
1064 |
return False |
1065 |
return True |
1066 |
|
1067 |
def Rename(self, new_id): |
1068 |
"""Rename a device.
|
1069 |
|
1070 |
This is not supported for drbd devices.
|
1071 |
|
1072 |
"""
|
1073 |
raise errors.ProgrammerError("Can't rename a drbd device") |
1074 |
|
1075 |
|
1076 |
class DRBDev(BaseDRBD): |
1077 |
"""DRBD block device.
|
1078 |
|
1079 |
This implements the local host part of the DRBD device, i.e. it
|
1080 |
doesn't do anything to the supposed peer. If you need a fully
|
1081 |
connected DRBD pair, you need to use this class on both hosts.
|
1082 |
|
1083 |
The unique_id for the drbd device is the (local_ip, local_port,
|
1084 |
remote_ip, remote_port) tuple, and it must have two children: the
|
1085 |
data device and the meta_device. The meta device is checked for
|
1086 |
valid size and is zeroed on create.
|
1087 |
|
1088 |
"""
|
1089 |
def __init__(self, unique_id, children): |
1090 |
super(DRBDev, self).__init__(unique_id, children) |
1091 |
self.major = self._DRBD_MAJOR |
1092 |
version = self._GetVersion()
|
1093 |
if version['k_major'] != 0 and version['k_minor'] != 7: |
1094 |
raise errors.BlockDeviceError("Mismatch in DRBD kernel version and" |
1095 |
" requested ganeti usage: kernel is"
|
1096 |
" %s.%s, ganeti wants 0.7" %
|
1097 |
(version['k_major'], version['k_minor'])) |
1098 |
if len(children) != 2: |
1099 |
raise ValueError("Invalid configuration data %s" % str(children)) |
1100 |
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 4: |
1101 |
raise ValueError("Invalid configuration data %s" % str(unique_id)) |
1102 |
self._lhost, self._lport, self._rhost, self._rport = unique_id |
1103 |
self.Attach()
|
1104 |
|
1105 |
@classmethod
|
1106 |
def _FindUnusedMinor(cls): |
1107 |
"""Find an unused DRBD device.
|
1108 |
|
1109 |
"""
|
1110 |
data = cls._GetProcData() |
1111 |
|
1112 |
valid_line = re.compile("^ *([0-9]+): cs:Unconfigured$")
|
1113 |
for line in data: |
1114 |
match = valid_line.match(line) |
1115 |
if match:
|
1116 |
return int(match.group(1)) |
1117 |
logger.Error("Error: no free drbd minors!")
|
1118 |
raise errors.BlockDeviceError("Can't find a free DRBD minor") |
1119 |
|
1120 |
@classmethod
|
1121 |
def _GetDevInfo(cls, minor): |
1122 |
"""Get details about a given DRBD minor.
|
1123 |
|
1124 |
This return, if available, the local backing device in (major,
|
1125 |
minor) formant and the local and remote (ip, port) information.
|
1126 |
|
1127 |
"""
|
1128 |
data = {} |
1129 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "show"]) |
1130 |
if result.failed:
|
1131 |
logger.Error("Can't display the drbd config: %s" % result.fail_reason)
|
1132 |
return data
|
1133 |
out = result.stdout |
1134 |
if out == "Not configured\n": |
1135 |
return data
|
1136 |
for line in out.splitlines(): |
1137 |
if "local_dev" not in data: |
1138 |
match = re.match("^Lower device: ([0-9]+):([0-9]+) .*$", line)
|
1139 |
if match:
|
1140 |
data["local_dev"] = (int(match.group(1)), int(match.group(2))) |
1141 |
continue
|
1142 |
if "meta_dev" not in data: |
1143 |
match = re.match("^Meta device: (([0-9]+):([0-9]+)|internal).*$", line)
|
1144 |
if match:
|
1145 |
if match.group(2) is not None and match.group(3) is not None: |
1146 |
# matched on the major/minor
|
1147 |
data["meta_dev"] = (int(match.group(2)), int(match.group(3))) |
1148 |
else:
|
1149 |
# matched on the "internal" string
|
1150 |
data["meta_dev"] = match.group(1) |
1151 |
# in this case, no meta_index is in the output
|
1152 |
data["meta_index"] = -1 |
1153 |
continue
|
1154 |
if "meta_index" not in data: |
1155 |
match = re.match("^Meta index: ([0-9]+).*$", line)
|
1156 |
if match:
|
1157 |
data["meta_index"] = int(match.group(1)) |
1158 |
continue
|
1159 |
if "local_addr" not in data: |
1160 |
match = re.match("^Local address: ([0-9.]+):([0-9]+)$", line)
|
1161 |
if match:
|
1162 |
data["local_addr"] = (match.group(1), int(match.group(2))) |
1163 |
continue
|
1164 |
if "remote_addr" not in data: |
1165 |
match = re.match("^Remote address: ([0-9.]+):([0-9]+)$", line)
|
1166 |
if match:
|
1167 |
data["remote_addr"] = (match.group(1), int(match.group(2))) |
1168 |
continue
|
1169 |
return data
|
1170 |
|
1171 |
def _MatchesLocal(self, info): |
1172 |
"""Test if our local config matches with an existing device.
|
1173 |
|
1174 |
The parameter should be as returned from `_GetDevInfo()`. This
|
1175 |
method tests if our local backing device is the same as the one in
|
1176 |
the info parameter, in effect testing if we look like the given
|
1177 |
device.
|
1178 |
|
1179 |
"""
|
1180 |
if not ("local_dev" in info and "meta_dev" in info and |
1181 |
"meta_index" in info): |
1182 |
return False |
1183 |
|
1184 |
backend = self._children[0] |
1185 |
if backend is not None: |
1186 |
retval = (info["local_dev"] == (backend.major, backend.minor))
|
1187 |
else:
|
1188 |
retval = (info["local_dev"] == (0, 0)) |
1189 |
meta = self._children[1] |
1190 |
if meta is not None: |
1191 |
retval = retval and (info["meta_dev"] == (meta.major, meta.minor)) |
1192 |
retval = retval and (info["meta_index"] == 0) |
1193 |
else:
|
1194 |
retval = retval and (info["meta_dev"] == "internal" and |
1195 |
info["meta_index"] == -1) |
1196 |
return retval
|
1197 |
|
1198 |
def _MatchesNet(self, info): |
1199 |
"""Test if our network config matches with an existing device.
|
1200 |
|
1201 |
The parameter should be as returned from `_GetDevInfo()`. This
|
1202 |
method tests if our network configuration is the same as the one
|
1203 |
in the info parameter, in effect testing if we look like the given
|
1204 |
device.
|
1205 |
|
1206 |
"""
|
1207 |
if (((self._lhost is None and not ("local_addr" in info)) and |
1208 |
(self._rhost is None and not ("remote_addr" in info)))): |
1209 |
return True |
1210 |
|
1211 |
if self._lhost is None: |
1212 |
return False |
1213 |
|
1214 |
if not ("local_addr" in info and |
1215 |
"remote_addr" in info): |
1216 |
return False |
1217 |
|
1218 |
retval = (info["local_addr"] == (self._lhost, self._lport)) |
1219 |
retval = (retval and
|
1220 |
info["remote_addr"] == (self._rhost, self._rport)) |
1221 |
return retval
|
1222 |
|
1223 |
@classmethod
|
1224 |
def _AssembleLocal(cls, minor, backend, meta): |
1225 |
"""Configure the local part of a DRBD device.
|
1226 |
|
1227 |
This is the first thing that must be done on an unconfigured DRBD
|
1228 |
device. And it must be done only once.
|
1229 |
|
1230 |
"""
|
1231 |
if not cls._CheckMetaSize(meta): |
1232 |
return False |
1233 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disk", |
1234 |
backend, meta, "0", "-e", "detach"]) |
1235 |
if result.failed:
|
1236 |
logger.Error("Can't attach local disk: %s" % result.output)
|
1237 |
return not result.failed |
1238 |
|
1239 |
@classmethod
|
1240 |
def _ShutdownLocal(cls, minor): |
1241 |
"""Detach from the local device.
|
1242 |
|
1243 |
I/Os will continue to be served from the remote device. If we
|
1244 |
don't have a remote device, this operation will fail.
|
1245 |
|
1246 |
"""
|
1247 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "detach"]) |
1248 |
if result.failed:
|
1249 |
logger.Error("Can't detach local device: %s" % result.output)
|
1250 |
return not result.failed |
1251 |
|
1252 |
@staticmethod
|
1253 |
def _ShutdownAll(minor): |
1254 |
"""Deactivate the device.
|
1255 |
|
1256 |
This will, of course, fail if the device is in use.
|
1257 |
|
1258 |
"""
|
1259 |
result = utils.RunCmd(["drbdsetup", DRBDev._DevPath(minor), "down"]) |
1260 |
if result.failed:
|
1261 |
logger.Error("Can't shutdown drbd device: %s" % result.output)
|
1262 |
return not result.failed |
1263 |
|
1264 |
@classmethod
|
1265 |
def _AssembleNet(cls, minor, net_info, protocol): |
1266 |
"""Configure the network part of the device.
|
1267 |
|
1268 |
This operation can be, in theory, done multiple times, but there
|
1269 |
have been cases (in lab testing) in which the network part of the
|
1270 |
device had become stuck and couldn't be shut down because activity
|
1271 |
from the new peer (also stuck) triggered a timer re-init and
|
1272 |
needed remote peer interface shutdown in order to clear. So please
|
1273 |
don't change online the net config.
|
1274 |
|
1275 |
"""
|
1276 |
lhost, lport, rhost, rport = net_info |
1277 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "net", |
1278 |
"%s:%s" % (lhost, lport), "%s:%s" % (rhost, rport), |
1279 |
protocol]) |
1280 |
if result.failed:
|
1281 |
logger.Error("Can't setup network for dbrd device: %s" %
|
1282 |
result.fail_reason) |
1283 |
return False |
1284 |
|
1285 |
timeout = time.time() + 10
|
1286 |
ok = False
|
1287 |
while time.time() < timeout:
|
1288 |
info = cls._GetDevInfo(minor) |
1289 |
if not "local_addr" in info or not "remote_addr" in info: |
1290 |
time.sleep(1)
|
1291 |
continue
|
1292 |
if (info["local_addr"] != (lhost, lport) or |
1293 |
info["remote_addr"] != (rhost, rport)):
|
1294 |
time.sleep(1)
|
1295 |
continue
|
1296 |
ok = True
|
1297 |
break
|
1298 |
if not ok: |
1299 |
logger.Error("Timeout while configuring network")
|
1300 |
return False |
1301 |
return True |
1302 |
|
1303 |
@classmethod
|
1304 |
def _ShutdownNet(cls, minor): |
1305 |
"""Disconnect from the remote peer.
|
1306 |
|
1307 |
This fails if we don't have a local device.
|
1308 |
|
1309 |
"""
|
1310 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disconnect"]) |
1311 |
if result.failed:
|
1312 |
logger.Error("Can't shutdown network: %s" % result.output)
|
1313 |
return not result.failed |
1314 |
|
1315 |
def Assemble(self): |
1316 |
"""Assemble the drbd.
|
1317 |
|
1318 |
Method:
|
1319 |
- if we have a local backing device, we bind to it by:
|
1320 |
- checking the list of used drbd devices
|
1321 |
- check if the local minor use of any of them is our own device
|
1322 |
- if yes, abort?
|
1323 |
- if not, bind
|
1324 |
- if we have a local/remote net info:
|
1325 |
- redo the local backing device step for the remote device
|
1326 |
- check if any drbd device is using the local port,
|
1327 |
if yes abort
|
1328 |
- check if any remote drbd device is using the remote
|
1329 |
port, if yes abort (for now)
|
1330 |
- bind our net port
|
1331 |
- bind the remote net port
|
1332 |
|
1333 |
"""
|
1334 |
self.Attach()
|
1335 |
if self.minor is not None: |
1336 |
logger.Info("Already assembled")
|
1337 |
return True |
1338 |
|
1339 |
result = super(DRBDev, self).Assemble() |
1340 |
if not result: |
1341 |
return result
|
1342 |
|
1343 |
minor = self._FindUnusedMinor()
|
1344 |
need_localdev_teardown = False
|
1345 |
if self._children[0]: |
1346 |
result = self._AssembleLocal(minor, self._children[0].dev_path, |
1347 |
self._children[1].dev_path) |
1348 |
if not result: |
1349 |
return False |
1350 |
need_localdev_teardown = True
|
1351 |
if self._lhost and self._lport and self._rhost and self._rport: |
1352 |
result = self._AssembleNet(minor,
|
1353 |
(self._lhost, self._lport, |
1354 |
self._rhost, self._rport), |
1355 |
"C")
|
1356 |
if not result: |
1357 |
if need_localdev_teardown:
|
1358 |
# we will ignore failures from this
|
1359 |
logger.Error("net setup failed, tearing down local device")
|
1360 |
self._ShutdownAll(minor)
|
1361 |
return False |
1362 |
self._SetFromMinor(minor)
|
1363 |
return True |
1364 |
|
1365 |
def Shutdown(self): |
1366 |
"""Shutdown the DRBD device.
|
1367 |
|
1368 |
"""
|
1369 |
if self.minor is None and not self.Attach(): |
1370 |
logger.Info("DRBD device not attached to a device during Shutdown")
|
1371 |
return True |
1372 |
if not self._ShutdownAll(self.minor): |
1373 |
return False |
1374 |
self.minor = None |
1375 |
self.dev_path = None |
1376 |
return True |
1377 |
|
1378 |
def Attach(self): |
1379 |
"""Find a DRBD device which matches our config and attach to it.
|
1380 |
|
1381 |
In case of partially attached (local device matches but no network
|
1382 |
setup), we perform the network attach. If successful, we re-test
|
1383 |
the attach if can return success.
|
1384 |
|
1385 |
"""
|
1386 |
for minor in self._GetUsedDevs(): |
1387 |
info = self._GetDevInfo(minor)
|
1388 |
match_l = self._MatchesLocal(info)
|
1389 |
match_r = self._MatchesNet(info)
|
1390 |
if match_l and match_r: |
1391 |
break
|
1392 |
if match_l and not match_r and "local_addr" not in info: |
1393 |
res_r = self._AssembleNet(minor,
|
1394 |
(self._lhost, self._lport, |
1395 |
self._rhost, self._rport), |
1396 |
"C")
|
1397 |
if res_r and self._MatchesNet(self._GetDevInfo(minor)): |
1398 |
break
|
1399 |
else:
|
1400 |
minor = None
|
1401 |
|
1402 |
self._SetFromMinor(minor)
|
1403 |
return minor is not None |
1404 |
|
1405 |
def Open(self, force=False): |
1406 |
"""Make the local state primary.
|
1407 |
|
1408 |
If the 'force' parameter is given, the '--do-what-I-say' parameter
|
1409 |
is given. Since this is a pottentialy dangerous operation, the
|
1410 |
force flag should be only given after creation, when it actually
|
1411 |
has to be given.
|
1412 |
|
1413 |
"""
|
1414 |
if self.minor is None and not self.Attach(): |
1415 |
logger.Error("DRBD cannot attach to a device during open")
|
1416 |
return False |
1417 |
cmd = ["drbdsetup", self.dev_path, "primary"] |
1418 |
if force:
|
1419 |
cmd.append("--do-what-I-say")
|
1420 |
result = utils.RunCmd(cmd) |
1421 |
if result.failed:
|
1422 |
msg = ("Can't make drbd device primary: %s" % result.output)
|
1423 |
logger.Error(msg) |
1424 |
raise errors.BlockDeviceError(msg)
|
1425 |
|
1426 |
def Close(self): |
1427 |
"""Make the local state secondary.
|
1428 |
|
1429 |
This will, of course, fail if the device is in use.
|
1430 |
|
1431 |
"""
|
1432 |
if self.minor is None and not self.Attach(): |
1433 |
logger.Info("Instance not attached to a device")
|
1434 |
raise errors.BlockDeviceError("Can't find device") |
1435 |
result = utils.RunCmd(["drbdsetup", self.dev_path, "secondary"]) |
1436 |
if result.failed:
|
1437 |
msg = ("Can't switch drbd device to"
|
1438 |
" secondary: %s" % result.output)
|
1439 |
logger.Error(msg) |
1440 |
raise errors.BlockDeviceError(msg)
|
1441 |
|
1442 |
def SetSyncSpeed(self, kbytes): |
1443 |
"""Set the speed of the DRBD syncer.
|
1444 |
|
1445 |
"""
|
1446 |
children_result = super(DRBDev, self).SetSyncSpeed(kbytes) |
1447 |
if self.minor is None: |
1448 |
logger.Info("Instance not attached to a device")
|
1449 |
return False |
1450 |
result = utils.RunCmd(["drbdsetup", self.dev_path, "syncer", "-r", "%d" % |
1451 |
kbytes]) |
1452 |
if result.failed:
|
1453 |
logger.Error("Can't change syncer rate: %s " % result.fail_reason)
|
1454 |
return not result.failed and children_result |
1455 |
|
1456 |
def GetSyncStatus(self): |
1457 |
"""Returns the sync status of the device.
|
1458 |
|
1459 |
Returns:
|
1460 |
(sync_percent, estimated_time, is_degraded, ldisk)
|
1461 |
|
1462 |
If sync_percent is None, it means all is ok
|
1463 |
If estimated_time is None, it means we can't esimate
|
1464 |
the time needed, otherwise it's the time left in seconds.
|
1465 |
|
1466 |
The ldisk parameter will be returned as True, since the DRBD7
|
1467 |
devices have not been converted.
|
1468 |
|
1469 |
"""
|
1470 |
if self.minor is None and not self.Attach(): |
1471 |
raise errors.BlockDeviceError("Can't attach to device in GetSyncStatus") |
1472 |
proc_info = self._MassageProcData(self._GetProcData()) |
1473 |
if self.minor not in proc_info: |
1474 |
raise errors.BlockDeviceError("Can't find myself in /proc (minor %d)" % |
1475 |
self.minor)
|
1476 |
line = proc_info[self.minor]
|
1477 |
match = re.match("^.*sync'ed: *([0-9.]+)%.*"
|
1478 |
" finish: ([0-9]+):([0-9]+):([0-9]+) .*$", line)
|
1479 |
if match:
|
1480 |
sync_percent = float(match.group(1)) |
1481 |
hours = int(match.group(2)) |
1482 |
minutes = int(match.group(3)) |
1483 |
seconds = int(match.group(4)) |
1484 |
est_time = hours * 3600 + minutes * 60 + seconds |
1485 |
else:
|
1486 |
sync_percent = None
|
1487 |
est_time = None
|
1488 |
match = re.match("^ *[0-9]+: cs:([^ ]+).*$", line)
|
1489 |
if not match: |
1490 |
raise errors.BlockDeviceError("Can't find my data in /proc (minor %d)" % |
1491 |
self.minor)
|
1492 |
client_state = match.group(1)
|
1493 |
is_degraded = client_state != "Connected"
|
1494 |
return sync_percent, est_time, is_degraded, False |
1495 |
|
1496 |
@staticmethod
|
1497 |
def _ZeroDevice(device): |
1498 |
"""Zero a device.
|
1499 |
|
1500 |
This writes until we get ENOSPC.
|
1501 |
|
1502 |
"""
|
1503 |
f = open(device, "w") |
1504 |
buf = "\0" * 1048576 |
1505 |
try:
|
1506 |
while True: |
1507 |
f.write(buf) |
1508 |
except IOError, err: |
1509 |
if err.errno != errno.ENOSPC:
|
1510 |
raise
|
1511 |
|
1512 |
@classmethod
|
1513 |
def Create(cls, unique_id, children, size): |
1514 |
"""Create a new DRBD device.
|
1515 |
|
1516 |
Since DRBD devices are not created per se, just assembled, this
|
1517 |
function just zeroes the meta device.
|
1518 |
|
1519 |
"""
|
1520 |
if len(children) != 2: |
1521 |
raise errors.ProgrammerError("Invalid setup for the drbd device") |
1522 |
meta = children[1]
|
1523 |
meta.Assemble() |
1524 |
if not meta.Attach(): |
1525 |
raise errors.BlockDeviceError("Can't attach to meta device") |
1526 |
if not cls._CheckMetaSize(meta.dev_path): |
1527 |
raise errors.BlockDeviceError("Invalid meta device") |
1528 |
logger.Info("Started zeroing device %s" % meta.dev_path)
|
1529 |
cls._ZeroDevice(meta.dev_path) |
1530 |
logger.Info("Done zeroing device %s" % meta.dev_path)
|
1531 |
return cls(unique_id, children)
|
1532 |
|
1533 |
def Remove(self): |
1534 |
"""Stub remove for DRBD devices.
|
1535 |
|
1536 |
"""
|
1537 |
return self.Shutdown() |
1538 |
|
1539 |
|
1540 |
class DRBD8(BaseDRBD): |
1541 |
"""DRBD v8.x block device.
|
1542 |
|
1543 |
This implements the local host part of the DRBD device, i.e. it
|
1544 |
doesn't do anything to the supposed peer. If you need a fully
|
1545 |
connected DRBD pair, you need to use this class on both hosts.
|
1546 |
|
1547 |
The unique_id for the drbd device is the (local_ip, local_port,
|
1548 |
remote_ip, remote_port) tuple, and it must have two children: the
|
1549 |
data device and the meta_device. The meta device is checked for
|
1550 |
valid size and is zeroed on create.
|
1551 |
|
1552 |
"""
|
1553 |
_MAX_MINORS = 255
|
1554 |
_PARSE_SHOW = None
|
1555 |
|
1556 |
def __init__(self, unique_id, children): |
1557 |
if children and children.count(None) > 0: |
1558 |
children = [] |
1559 |
super(DRBD8, self).__init__(unique_id, children) |
1560 |
self.major = self._DRBD_MAJOR |
1561 |
version = self._GetVersion()
|
1562 |
if version['k_major'] != 8 : |
1563 |
raise errors.BlockDeviceError("Mismatch in DRBD kernel version and" |
1564 |
" requested ganeti usage: kernel is"
|
1565 |
" %s.%s, ganeti wants 8.x" %
|
1566 |
(version['k_major'], version['k_minor'])) |
1567 |
|
1568 |
if len(children) not in (0, 2): |
1569 |
raise ValueError("Invalid configuration data %s" % str(children)) |
1570 |
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 4: |
1571 |
raise ValueError("Invalid configuration data %s" % str(unique_id)) |
1572 |
self._lhost, self._lport, self._rhost, self._rport = unique_id |
1573 |
self.Attach()
|
1574 |
|
1575 |
@classmethod
|
1576 |
def _InitMeta(cls, minor, dev_path): |
1577 |
"""Initialize a meta device.
|
1578 |
|
1579 |
This will not work if the given minor is in use.
|
1580 |
|
1581 |
"""
|
1582 |
result = utils.RunCmd(["drbdmeta", "--force", cls._DevPath(minor), |
1583 |
"v08", dev_path, "0", "create-md"]) |
1584 |
if result.failed:
|
1585 |
raise errors.BlockDeviceError("Can't initialize meta device: %s" % |
1586 |
result.output) |
1587 |
|
1588 |
@classmethod
|
1589 |
def _FindUnusedMinor(cls): |
1590 |
"""Find an unused DRBD device.
|
1591 |
|
1592 |
This is specific to 8.x as the minors are allocated dynamically,
|
1593 |
so non-existing numbers up to a max minor count are actually free.
|
1594 |
|
1595 |
"""
|
1596 |
data = cls._GetProcData() |
1597 |
|
1598 |
unused_line = re.compile("^ *([0-9]+): cs:Unconfigured$")
|
1599 |
used_line = re.compile("^ *([0-9]+): cs:")
|
1600 |
highest = None
|
1601 |
for line in data: |
1602 |
match = unused_line.match(line) |
1603 |
if match:
|
1604 |
return int(match.group(1)) |
1605 |
match = used_line.match(line) |
1606 |
if match:
|
1607 |
minor = int(match.group(1)) |
1608 |
highest = max(highest, minor)
|
1609 |
if highest is None: # there are no minors in use at all |
1610 |
return 0 |
1611 |
if highest >= cls._MAX_MINORS:
|
1612 |
logger.Error("Error: no free drbd minors!")
|
1613 |
raise errors.BlockDeviceError("Can't find a free DRBD minor") |
1614 |
return highest + 1 |
1615 |
|
1616 |
@classmethod
|
1617 |
def _IsValidMeta(cls, meta_device): |
1618 |
"""Check if the given meta device looks like a valid one.
|
1619 |
|
1620 |
"""
|
1621 |
minor = cls._FindUnusedMinor() |
1622 |
minor_path = cls._DevPath(minor) |
1623 |
result = utils.RunCmd(["drbdmeta", minor_path,
|
1624 |
"v08", meta_device, "0", |
1625 |
"dstate"])
|
1626 |
if result.failed:
|
1627 |
logger.Error("Invalid meta device %s: %s" % (meta_device, result.output))
|
1628 |
return False |
1629 |
return True |
1630 |
|
1631 |
@classmethod
|
1632 |
def _GetShowParser(cls): |
1633 |
"""Return a parser for `drbd show` output.
|
1634 |
|
1635 |
This will either create or return an already-create parser for the
|
1636 |
output of the command `drbd show`.
|
1637 |
|
1638 |
"""
|
1639 |
if cls._PARSE_SHOW is not None: |
1640 |
return cls._PARSE_SHOW
|
1641 |
|
1642 |
# pyparsing setup
|
1643 |
lbrace = pyp.Literal("{").suppress()
|
1644 |
rbrace = pyp.Literal("}").suppress()
|
1645 |
semi = pyp.Literal(";").suppress()
|
1646 |
# this also converts the value to an int
|
1647 |
number = pyp.Word(pyp.nums).setParseAction(lambda s, l, t: int(t[0])) |
1648 |
|
1649 |
comment = pyp.Literal ("#") + pyp.Optional(pyp.restOfLine)
|
1650 |
defa = pyp.Literal("_is_default").suppress()
|
1651 |
dbl_quote = pyp.Literal('"').suppress()
|
1652 |
|
1653 |
keyword = pyp.Word(pyp.alphanums + '-')
|
1654 |
|
1655 |
# value types
|
1656 |
value = pyp.Word(pyp.alphanums + '_-/.:')
|
1657 |
quoted = dbl_quote + pyp.CharsNotIn('"') + dbl_quote
|
1658 |
addr_port = (pyp.Word(pyp.nums + '.') + pyp.Literal(':').suppress() + |
1659 |
number) |
1660 |
# meta device, extended syntax
|
1661 |
meta_value = ((value ^ quoted) + pyp.Literal('[').suppress() +
|
1662 |
number + pyp.Word(']').suppress())
|
1663 |
|
1664 |
# a statement
|
1665 |
stmt = (~rbrace + keyword + ~lbrace + |
1666 |
(addr_port ^ value ^ quoted ^ meta_value) + |
1667 |
pyp.Optional(defa) + semi + |
1668 |
pyp.Optional(pyp.restOfLine).suppress()) |
1669 |
|
1670 |
# an entire section
|
1671 |
section_name = pyp.Word(pyp.alphas + '_')
|
1672 |
section = section_name + lbrace + pyp.ZeroOrMore(pyp.Group(stmt)) + rbrace |
1673 |
|
1674 |
bnf = pyp.ZeroOrMore(pyp.Group(section ^ stmt)) |
1675 |
bnf.ignore(comment) |
1676 |
|
1677 |
cls._PARSE_SHOW = bnf |
1678 |
|
1679 |
return bnf
|
1680 |
|
1681 |
@classmethod
|
1682 |
def _GetShowData(cls, minor): |
1683 |
"""Return the `drbdsetup show` data for a minor.
|
1684 |
|
1685 |
"""
|
1686 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "show"]) |
1687 |
if result.failed:
|
1688 |
logger.Error("Can't display the drbd config: %s" % result.fail_reason)
|
1689 |
return None |
1690 |
return result.stdout
|
1691 |
|
1692 |
@classmethod
|
1693 |
def _GetDevInfo(cls, out): |
1694 |
"""Parse details about a given DRBD minor.
|
1695 |
|
1696 |
This return, if available, the local backing device (as a path)
|
1697 |
and the local and remote (ip, port) information from a string
|
1698 |
containing the output of the `drbdsetup show` command as returned
|
1699 |
by _GetShowData.
|
1700 |
|
1701 |
"""
|
1702 |
data = {} |
1703 |
if not out: |
1704 |
return data
|
1705 |
|
1706 |
bnf = cls._GetShowParser() |
1707 |
# run pyparse
|
1708 |
|
1709 |
try:
|
1710 |
results = bnf.parseString(out) |
1711 |
except pyp.ParseException, err:
|
1712 |
raise errors.BlockDeviceError("Can't parse drbdsetup show output: %s" % |
1713 |
str(err))
|
1714 |
|
1715 |
# and massage the results into our desired format
|
1716 |
for section in results: |
1717 |
sname = section[0]
|
1718 |
if sname == "_this_host": |
1719 |
for lst in section[1:]: |
1720 |
if lst[0] == "disk": |
1721 |
data["local_dev"] = lst[1] |
1722 |
elif lst[0] == "meta-disk": |
1723 |
data["meta_dev"] = lst[1] |
1724 |
data["meta_index"] = lst[2] |
1725 |
elif lst[0] == "address": |
1726 |
data["local_addr"] = tuple(lst[1:]) |
1727 |
elif sname == "_remote_host": |
1728 |
for lst in section[1:]: |
1729 |
if lst[0] == "address": |
1730 |
data["remote_addr"] = tuple(lst[1:]) |
1731 |
return data
|
1732 |
|
1733 |
def _MatchesLocal(self, info): |
1734 |
"""Test if our local config matches with an existing device.
|
1735 |
|
1736 |
The parameter should be as returned from `_GetDevInfo()`. This
|
1737 |
method tests if our local backing device is the same as the one in
|
1738 |
the info parameter, in effect testing if we look like the given
|
1739 |
device.
|
1740 |
|
1741 |
"""
|
1742 |
if self._children: |
1743 |
backend, meta = self._children
|
1744 |
else:
|
1745 |
backend = meta = None
|
1746 |
|
1747 |
if backend is not None: |
1748 |
retval = ("local_dev" in info and info["local_dev"] == backend.dev_path) |
1749 |
else:
|
1750 |
retval = ("local_dev" not in info) |
1751 |
|
1752 |
if meta is not None: |
1753 |
retval = retval and ("meta_dev" in info and |
1754 |
info["meta_dev"] == meta.dev_path)
|
1755 |
retval = retval and ("meta_index" in info and |
1756 |
info["meta_index"] == 0) |
1757 |
else:
|
1758 |
retval = retval and ("meta_dev" not in info and |
1759 |
"meta_index" not in info) |
1760 |
return retval
|
1761 |
|
1762 |
def _MatchesNet(self, info): |
1763 |
"""Test if our network config matches with an existing device.
|
1764 |
|
1765 |
The parameter should be as returned from `_GetDevInfo()`. This
|
1766 |
method tests if our network configuration is the same as the one
|
1767 |
in the info parameter, in effect testing if we look like the given
|
1768 |
device.
|
1769 |
|
1770 |
"""
|
1771 |
if (((self._lhost is None and not ("local_addr" in info)) and |
1772 |
(self._rhost is None and not ("remote_addr" in info)))): |
1773 |
return True |
1774 |
|
1775 |
if self._lhost is None: |
1776 |
return False |
1777 |
|
1778 |
if not ("local_addr" in info and |
1779 |
"remote_addr" in info): |
1780 |
return False |
1781 |
|
1782 |
retval = (info["local_addr"] == (self._lhost, self._lport)) |
1783 |
retval = (retval and
|
1784 |
info["remote_addr"] == (self._rhost, self._rport)) |
1785 |
return retval
|
1786 |
|
1787 |
@classmethod
|
1788 |
def _AssembleLocal(cls, minor, backend, meta): |
1789 |
"""Configure the local part of a DRBD device.
|
1790 |
|
1791 |
This is the first thing that must be done on an unconfigured DRBD
|
1792 |
device. And it must be done only once.
|
1793 |
|
1794 |
"""
|
1795 |
if not cls._IsValidMeta(meta): |
1796 |
return False |
1797 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disk", |
1798 |
backend, meta, "0", "-e", "detach", |
1799 |
"--create-device"])
|
1800 |
if result.failed:
|
1801 |
logger.Error("Can't attach local disk: %s" % result.output)
|
1802 |
return not result.failed |
1803 |
|
1804 |
@classmethod
|
1805 |
def _AssembleNet(cls, minor, net_info, protocol, |
1806 |
dual_pri=False, hmac=None, secret=None): |
1807 |
"""Configure the network part of the device.
|
1808 |
|
1809 |
"""
|
1810 |
lhost, lport, rhost, rport = net_info |
1811 |
if None in net_info: |
1812 |
# we don't want network connection and actually want to make
|
1813 |
# sure its shutdown
|
1814 |
return cls._ShutdownNet(minor)
|
1815 |
|
1816 |
args = ["drbdsetup", cls._DevPath(minor), "net", |
1817 |
"%s:%s" % (lhost, lport), "%s:%s" % (rhost, rport), protocol, |
1818 |
"-A", "discard-zero-changes", |
1819 |
"-B", "consensus", |
1820 |
] |
1821 |
if dual_pri:
|
1822 |
args.append("-m")
|
1823 |
if hmac and secret: |
1824 |
args.extend(["-a", hmac, "-x", secret]) |
1825 |
result = utils.RunCmd(args) |
1826 |
if result.failed:
|
1827 |
logger.Error("Can't setup network for dbrd device: %s" %
|
1828 |
result.fail_reason) |
1829 |
return False |
1830 |
|
1831 |
timeout = time.time() + 10
|
1832 |
ok = False
|
1833 |
while time.time() < timeout:
|
1834 |
info = cls._GetDevInfo(cls._GetShowData(minor)) |
1835 |
if not "local_addr" in info or not "remote_addr" in info: |
1836 |
time.sleep(1)
|
1837 |
continue
|
1838 |
if (info["local_addr"] != (lhost, lport) or |
1839 |
info["remote_addr"] != (rhost, rport)):
|
1840 |
time.sleep(1)
|
1841 |
continue
|
1842 |
ok = True
|
1843 |
break
|
1844 |
if not ok: |
1845 |
logger.Error("Timeout while configuring network")
|
1846 |
return False |
1847 |
return True |
1848 |
|
1849 |
def AddChildren(self, devices): |
1850 |
"""Add a disk to the DRBD device.
|
1851 |
|
1852 |
"""
|
1853 |
if self.minor is None: |
1854 |
raise errors.BlockDeviceError("Can't attach to dbrd8 during AddChildren") |
1855 |
if len(devices) != 2: |
1856 |
raise errors.BlockDeviceError("Need two devices for AddChildren") |
1857 |
info = self._GetDevInfo(self._GetShowData(self.minor)) |
1858 |
if "local_dev" in info: |
1859 |
raise errors.BlockDeviceError("DRBD8 already attached to a local disk") |
1860 |
backend, meta = devices |
1861 |
if backend.dev_path is None or meta.dev_path is None: |
1862 |
raise errors.BlockDeviceError("Children not ready during AddChildren") |
1863 |
backend.Open() |
1864 |
meta.Open() |
1865 |
if not self._CheckMetaSize(meta.dev_path): |
1866 |
raise errors.BlockDeviceError("Invalid meta device size") |
1867 |
self._InitMeta(self._FindUnusedMinor(), meta.dev_path) |
1868 |
if not self._IsValidMeta(meta.dev_path): |
1869 |
raise errors.BlockDeviceError("Cannot initalize meta device") |
1870 |
|
1871 |
if not self._AssembleLocal(self.minor, backend.dev_path, meta.dev_path): |
1872 |
raise errors.BlockDeviceError("Can't attach to local storage") |
1873 |
self._children = devices
|
1874 |
|
1875 |
def RemoveChildren(self, devices): |
1876 |
"""Detach the drbd device from local storage.
|
1877 |
|
1878 |
"""
|
1879 |
if self.minor is None: |
1880 |
raise errors.BlockDeviceError("Can't attach to drbd8 during" |
1881 |
" RemoveChildren")
|
1882 |
# early return if we don't actually have backing storage
|
1883 |
info = self._GetDevInfo(self._GetShowData(self.minor)) |
1884 |
if "local_dev" not in info: |
1885 |
return
|
1886 |
if len(self._children) != 2: |
1887 |
raise errors.BlockDeviceError("We don't have two children: %s" % |
1888 |
self._children)
|
1889 |
if self._children.count(None) == 2: # we don't actually have children :) |
1890 |
logger.Error("Requested detach while detached")
|
1891 |
return
|
1892 |
if len(devices) != 2: |
1893 |
raise errors.BlockDeviceError("We need two children in RemoveChildren") |
1894 |
for child, dev in zip(self._children, devices): |
1895 |
if dev != child.dev_path:
|
1896 |
raise errors.BlockDeviceError("Mismatch in local storage" |
1897 |
" (%s != %s) in RemoveChildren" %
|
1898 |
(dev, child.dev_path)) |
1899 |
|
1900 |
if not self._ShutdownLocal(self.minor): |
1901 |
raise errors.BlockDeviceError("Can't detach from local storage") |
1902 |
self._children = []
|
1903 |
|
1904 |
def SetSyncSpeed(self, kbytes): |
1905 |
"""Set the speed of the DRBD syncer.
|
1906 |
|
1907 |
"""
|
1908 |
children_result = super(DRBD8, self).SetSyncSpeed(kbytes) |
1909 |
if self.minor is None: |
1910 |
logger.Info("Instance not attached to a device")
|
1911 |
return False |
1912 |
result = utils.RunCmd(["drbdsetup", self.dev_path, "syncer", "-r", "%d" % |
1913 |
kbytes]) |
1914 |
if result.failed:
|
1915 |
logger.Error("Can't change syncer rate: %s " % result.fail_reason)
|
1916 |
return not result.failed and children_result |
1917 |
|
1918 |
def GetSyncStatus(self): |
1919 |
"""Returns the sync status of the device.
|
1920 |
|
1921 |
Returns:
|
1922 |
(sync_percent, estimated_time, is_degraded)
|
1923 |
|
1924 |
If sync_percent is None, it means all is ok
|
1925 |
If estimated_time is None, it means we can't esimate
|
1926 |
the time needed, otherwise it's the time left in seconds.
|
1927 |
|
1928 |
|
1929 |
We set the is_degraded parameter to True on two conditions:
|
1930 |
network not connected or local disk missing.
|
1931 |
|
1932 |
We compute the ldisk parameter based on wheter we have a local
|
1933 |
disk or not.
|
1934 |
|
1935 |
"""
|
1936 |
if self.minor is None and not self.Attach(): |
1937 |
raise errors.BlockDeviceError("Can't attach to device in GetSyncStatus") |
1938 |
proc_info = self._MassageProcData(self._GetProcData()) |
1939 |
if self.minor not in proc_info: |
1940 |
raise errors.BlockDeviceError("Can't find myself in /proc (minor %d)" % |
1941 |
self.minor)
|
1942 |
line = proc_info[self.minor]
|
1943 |
match = re.match("^.*sync'ed: *([0-9.]+)%.*"
|
1944 |
" finish: ([0-9]+):([0-9]+):([0-9]+) .*$", line)
|
1945 |
if match:
|
1946 |
sync_percent = float(match.group(1)) |
1947 |
hours = int(match.group(2)) |
1948 |
minutes = int(match.group(3)) |
1949 |
seconds = int(match.group(4)) |
1950 |
est_time = hours * 3600 + minutes * 60 + seconds |
1951 |
else:
|
1952 |
sync_percent = None
|
1953 |
est_time = None
|
1954 |
match = re.match("^ *\d+: cs:(\w+).*ds:(\w+)/(\w+).*$", line)
|
1955 |
if not match: |
1956 |
raise errors.BlockDeviceError("Can't find my data in /proc (minor %d)" % |
1957 |
self.minor)
|
1958 |
client_state = match.group(1)
|
1959 |
local_disk_state = match.group(2)
|
1960 |
ldisk = local_disk_state != "UpToDate"
|
1961 |
is_degraded = client_state != "Connected"
|
1962 |
return sync_percent, est_time, is_degraded or ldisk, ldisk |
1963 |
|
1964 |
def Open(self, force=False): |
1965 |
"""Make the local state primary.
|
1966 |
|
1967 |
If the 'force' parameter is given, the '--do-what-I-say' parameter
|
1968 |
is given. Since this is a pottentialy dangerous operation, the
|
1969 |
force flag should be only given after creation, when it actually
|
1970 |
has to be given.
|
1971 |
|
1972 |
"""
|
1973 |
if self.minor is None and not self.Attach(): |
1974 |
logger.Error("DRBD cannot attach to a device during open")
|
1975 |
return False |
1976 |
cmd = ["drbdsetup", self.dev_path, "primary"] |
1977 |
if force:
|
1978 |
cmd.append("-o")
|
1979 |
result = utils.RunCmd(cmd) |
1980 |
if result.failed:
|
1981 |
msg = ("Can't make drbd device primary: %s" % result.output)
|
1982 |
logger.Error(msg) |
1983 |
raise errors.BlockDeviceError(msg)
|
1984 |
|
1985 |
def Close(self): |
1986 |
"""Make the local state secondary.
|
1987 |
|
1988 |
This will, of course, fail if the device is in use.
|
1989 |
|
1990 |
"""
|
1991 |
if self.minor is None and not self.Attach(): |
1992 |
logger.Info("Instance not attached to a device")
|
1993 |
raise errors.BlockDeviceError("Can't find device") |
1994 |
result = utils.RunCmd(["drbdsetup", self.dev_path, "secondary"]) |
1995 |
if result.failed:
|
1996 |
msg = ("Can't switch drbd device to"
|
1997 |
" secondary: %s" % result.output)
|
1998 |
logger.Error(msg) |
1999 |
raise errors.BlockDeviceError(msg)
|
2000 |
|
2001 |
def Attach(self): |
2002 |
"""Find a DRBD device which matches our config and attach to it.
|
2003 |
|
2004 |
In case of partially attached (local device matches but no network
|
2005 |
setup), we perform the network attach. If successful, we re-test
|
2006 |
the attach if can return success.
|
2007 |
|
2008 |
"""
|
2009 |
for minor in self._GetUsedDevs(): |
2010 |
info = self._GetDevInfo(self._GetShowData(minor)) |
2011 |
match_l = self._MatchesLocal(info)
|
2012 |
match_r = self._MatchesNet(info)
|
2013 |
if match_l and match_r: |
2014 |
break
|
2015 |
if match_l and not match_r and "local_addr" not in info: |
2016 |
res_r = self._AssembleNet(minor,
|
2017 |
(self._lhost, self._lport, |
2018 |
self._rhost, self._rport), |
2019 |
"C")
|
2020 |
if res_r:
|
2021 |
if self._MatchesNet(self._GetDevInfo(self._GetShowData(minor))): |
2022 |
break
|
2023 |
# the weakest case: we find something that is only net attached
|
2024 |
# even though we were passed some children at init time
|
2025 |
if match_r and "local_dev" not in info: |
2026 |
break
|
2027 |
if match_l and not match_r and "local_addr" in info: |
2028 |
# strange case - the device network part points to somewhere
|
2029 |
# else, even though its local storage is ours; as we own the
|
2030 |
# drbd space, we try to disconnect from the remote peer and
|
2031 |
# reconnect to our correct one
|
2032 |
if not self._ShutdownNet(minor): |
2033 |
raise errors.BlockDeviceError("Device has correct local storage," |
2034 |
" wrong remote peer and is unable to"
|
2035 |
" disconnect in order to attach to"
|
2036 |
" the correct peer")
|
2037 |
# note: _AssembleNet also handles the case when we don't want
|
2038 |
# local storage (i.e. one or more of the _[lr](host|port) is
|
2039 |
# None)
|
2040 |
if (self._AssembleNet(minor, (self._lhost, self._lport, |
2041 |
self._rhost, self._rport), "C") and |
2042 |
self._MatchesNet(self._GetDevInfo(self._GetShowData(minor)))): |
2043 |
break
|
2044 |
|
2045 |
else:
|
2046 |
minor = None
|
2047 |
|
2048 |
self._SetFromMinor(minor)
|
2049 |
return minor is not None |
2050 |
|
2051 |
def Assemble(self): |
2052 |
"""Assemble the drbd.
|
2053 |
|
2054 |
Method:
|
2055 |
- if we have a local backing device, we bind to it by:
|
2056 |
- checking the list of used drbd devices
|
2057 |
- check if the local minor use of any of them is our own device
|
2058 |
- if yes, abort?
|
2059 |
- if not, bind
|
2060 |
- if we have a local/remote net info:
|
2061 |
- redo the local backing device step for the remote device
|
2062 |
- check if any drbd device is using the local port,
|
2063 |
if yes abort
|
2064 |
- check if any remote drbd device is using the remote
|
2065 |
port, if yes abort (for now)
|
2066 |
- bind our net port
|
2067 |
- bind the remote net port
|
2068 |
|
2069 |
"""
|
2070 |
self.Attach()
|
2071 |
if self.minor is not None: |
2072 |
logger.Info("Already assembled")
|
2073 |
return True |
2074 |
|
2075 |
result = super(DRBD8, self).Assemble() |
2076 |
if not result: |
2077 |
return result
|
2078 |
|
2079 |
minor = self._FindUnusedMinor()
|
2080 |
need_localdev_teardown = False
|
2081 |
if self._children and self._children[0] and self._children[1]: |
2082 |
result = self._AssembleLocal(minor, self._children[0].dev_path, |
2083 |
self._children[1].dev_path) |
2084 |
if not result: |
2085 |
return False |
2086 |
need_localdev_teardown = True
|
2087 |
if self._lhost and self._lport and self._rhost and self._rport: |
2088 |
result = self._AssembleNet(minor,
|
2089 |
(self._lhost, self._lport, |
2090 |
self._rhost, self._rport), |
2091 |
"C")
|
2092 |
if not result: |
2093 |
if need_localdev_teardown:
|
2094 |
# we will ignore failures from this
|
2095 |
logger.Error("net setup failed, tearing down local device")
|
2096 |
self._ShutdownAll(minor)
|
2097 |
return False |
2098 |
self._SetFromMinor(minor)
|
2099 |
return True |
2100 |
|
2101 |
@classmethod
|
2102 |
def _ShutdownLocal(cls, minor): |
2103 |
"""Detach from the local device.
|
2104 |
|
2105 |
I/Os will continue to be served from the remote device. If we
|
2106 |
don't have a remote device, this operation will fail.
|
2107 |
|
2108 |
"""
|
2109 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "detach"]) |
2110 |
if result.failed:
|
2111 |
logger.Error("Can't detach local device: %s" % result.output)
|
2112 |
return not result.failed |
2113 |
|
2114 |
@classmethod
|
2115 |
def _ShutdownNet(cls, minor): |
2116 |
"""Disconnect from the remote peer.
|
2117 |
|
2118 |
This fails if we don't have a local device.
|
2119 |
|
2120 |
"""
|
2121 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "disconnect"]) |
2122 |
if result.failed:
|
2123 |
logger.Error("Can't shutdown network: %s" % result.output)
|
2124 |
return not result.failed |
2125 |
|
2126 |
@classmethod
|
2127 |
def _ShutdownAll(cls, minor): |
2128 |
"""Deactivate the device.
|
2129 |
|
2130 |
This will, of course, fail if the device is in use.
|
2131 |
|
2132 |
"""
|
2133 |
result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "down"]) |
2134 |
if result.failed:
|
2135 |
logger.Error("Can't shutdown drbd device: %s" % result.output)
|
2136 |
return not result.failed |
2137 |
|
2138 |
def Shutdown(self): |
2139 |
"""Shutdown the DRBD device.
|
2140 |
|
2141 |
"""
|
2142 |
if self.minor is None and not self.Attach(): |
2143 |
logger.Info("DRBD device not attached to a device during Shutdown")
|
2144 |
return True |
2145 |
if not self._ShutdownAll(self.minor): |
2146 |
return False |
2147 |
self.minor = None |
2148 |
self.dev_path = None |
2149 |
return True |
2150 |
|
2151 |
def Remove(self): |
2152 |
"""Stub remove for DRBD devices.
|
2153 |
|
2154 |
"""
|
2155 |
return self.Shutdown() |
2156 |
|
2157 |
@classmethod
|
2158 |
def Create(cls, unique_id, children, size): |
2159 |
"""Create a new DRBD8 device.
|
2160 |
|
2161 |
Since DRBD devices are not created per se, just assembled, this
|
2162 |
function only initializes the metadata.
|
2163 |
|
2164 |
"""
|
2165 |
if len(children) != 2: |
2166 |
raise errors.ProgrammerError("Invalid setup for the drbd device") |
2167 |
meta = children[1]
|
2168 |
meta.Assemble() |
2169 |
if not meta.Attach(): |
2170 |
raise errors.BlockDeviceError("Can't attach to meta device") |
2171 |
if not cls._CheckMetaSize(meta.dev_path): |
2172 |
raise errors.BlockDeviceError("Invalid meta device size") |
2173 |
cls._InitMeta(cls._FindUnusedMinor(), meta.dev_path) |
2174 |
if not cls._IsValidMeta(meta.dev_path): |
2175 |
raise errors.BlockDeviceError("Cannot initalize meta device") |
2176 |
return cls(unique_id, children)
|
2177 |
|
2178 |
|
2179 |
class FileStorage(BlockDev): |
2180 |
"""File device.
|
2181 |
|
2182 |
This class represents the a file storage backend device.
|
2183 |
|
2184 |
The unique_id for the file device is a (file_driver, file_path) tuple.
|
2185 |
|
2186 |
"""
|
2187 |
def __init__(self, unique_id, children): |
2188 |
"""Initalizes a file device backend.
|
2189 |
|
2190 |
"""
|
2191 |
if children:
|
2192 |
raise errors.BlockDeviceError("Invalid setup for file device") |
2193 |
super(FileStorage, self).__init__(unique_id, children) |
2194 |
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2: |
2195 |
raise ValueError("Invalid configuration data %s" % str(unique_id)) |
2196 |
self.driver = unique_id[0] |
2197 |
self.dev_path = unique_id[1] |
2198 |
|
2199 |
def Assemble(self): |
2200 |
"""Assemble the device.
|
2201 |
|
2202 |
Checks whether the file device exists, raises BlockDeviceError otherwise.
|
2203 |
|
2204 |
"""
|
2205 |
if not os.path.exists(self.dev_path): |
2206 |
raise errors.BlockDeviceError("File device '%s' does not exist." % |
2207 |
self.dev_path)
|
2208 |
return True |
2209 |
|
2210 |
def Shutdown(self): |
2211 |
"""Shutdown the device.
|
2212 |
|
2213 |
This is a no-op for the file type, as we don't deacivate
|
2214 |
the file on shutdown.
|
2215 |
|
2216 |
"""
|
2217 |
return True |
2218 |
|
2219 |
def Open(self, force=False): |
2220 |
"""Make the device ready for I/O.
|
2221 |
|
2222 |
This is a no-op for the file type.
|
2223 |
|
2224 |
"""
|
2225 |
pass
|
2226 |
|
2227 |
def Close(self): |
2228 |
"""Notifies that the device will no longer be used for I/O.
|
2229 |
|
2230 |
This is a no-op for the file type.
|
2231 |
|
2232 |
"""
|
2233 |
pass
|
2234 |
|
2235 |
def Remove(self): |
2236 |
"""Remove the file backing the block device.
|
2237 |
|
2238 |
Returns:
|
2239 |
boolean indicating wheter removal of file was successful or not.
|
2240 |
|
2241 |
"""
|
2242 |
if not os.path.exists(self.dev_path): |
2243 |
return True |
2244 |
try:
|
2245 |
os.remove(self.dev_path)
|
2246 |
return True |
2247 |
except OSError, err: |
2248 |
logger.Error("Can't remove file '%s': %s"
|
2249 |
% (self.dev_path, err))
|
2250 |
return False |
2251 |
|
2252 |
def Attach(self): |
2253 |
"""Attach to an existing file.
|
2254 |
|
2255 |
Check if this file already exists.
|
2256 |
|
2257 |
Returns:
|
2258 |
boolean indicating if file exists or not.
|
2259 |
|
2260 |
"""
|
2261 |
if os.path.exists(self.dev_path): |
2262 |
return True |
2263 |
return False |
2264 |
|
2265 |
@classmethod
|
2266 |
def Create(cls, unique_id, children, size): |
2267 |
"""Create a new file.
|
2268 |
|
2269 |
Args:
|
2270 |
children:
|
2271 |
size: integer size of file in MiB
|
2272 |
|
2273 |
Returns:
|
2274 |
A ganeti.bdev.FileStorage object.
|
2275 |
|
2276 |
"""
|
2277 |
if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2: |
2278 |
raise ValueError("Invalid configuration data %s" % str(unique_id)) |
2279 |
dev_path = unique_id[1]
|
2280 |
try:
|
2281 |
f = open(dev_path, 'w') |
2282 |
except IOError, err: |
2283 |
raise errors.BlockDeviceError("Could not create '%'" % err) |
2284 |
else:
|
2285 |
f.truncate(size * 1024 * 1024) |
2286 |
f.close() |
2287 |
|
2288 |
return FileStorage(unique_id, children)
|
2289 |
|
2290 |
|
2291 |
DEV_MAP = { |
2292 |
constants.LD_LV: LogicalVolume, |
2293 |
constants.LD_MD_R1: MDRaid1, |
2294 |
constants.LD_DRBD7: DRBDev, |
2295 |
constants.LD_DRBD8: DRBD8, |
2296 |
constants.LD_FILE: FileStorage, |
2297 |
} |
2298 |
|
2299 |
|
2300 |
def FindDevice(dev_type, unique_id, children): |
2301 |
"""Search for an existing, assembled device.
|
2302 |
|
2303 |
This will succeed only if the device exists and is assembled, but it
|
2304 |
does not do any actions in order to activate the device.
|
2305 |
|
2306 |
"""
|
2307 |
if dev_type not in DEV_MAP: |
2308 |
raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type) |
2309 |
device = DEV_MAP[dev_type](unique_id, children) |
2310 |
if not device.Attach(): |
2311 |
return None |
2312 |
return device
|
2313 |
|
2314 |
|
2315 |
def AttachOrAssemble(dev_type, unique_id, children): |
2316 |
"""Try to attach or assemble an existing device.
|
2317 |
|
2318 |
This will attach to an existing assembled device or will assemble
|
2319 |
the device, as needed, to bring it fully up.
|
2320 |
|
2321 |
"""
|
2322 |
if dev_type not in DEV_MAP: |
2323 |
raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type) |
2324 |
device = DEV_MAP[dev_type](unique_id, children) |
2325 |
if not device.Attach(): |
2326 |
device.Assemble() |
2327 |
if not device.Attach(): |
2328 |
raise errors.BlockDeviceError("Can't find a valid block device for" |
2329 |
" %s/%s/%s" %
|
2330 |
(dev_type, unique_id, children)) |
2331 |
return device
|
2332 |
|
2333 |
|
2334 |
def Create(dev_type, unique_id, children, size): |
2335 |
"""Create a device.
|
2336 |
|
2337 |
"""
|
2338 |
if dev_type not in DEV_MAP: |
2339 |
raise errors.ProgrammerError("Invalid block device type '%s'" % dev_type) |
2340 |
device = DEV_MAP[dev_type].Create(unique_id, children, size) |
2341 |
return device
|