Package ganeti :: Package storage :: Module bdev :: Class RADOSBlockDevice
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Class RADOSBlockDevice

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A RADOS Block Device (rbd).

This class implements the RADOS Block Device for the backend. You need the rbd kernel driver, the RADOS Tools and a working RADOS cluster for this to be functional.

Instance Methods [hide private]
 
__init__(self, unique_id, children, size, params, dyn_params, *args)
Attaches to an rbd device.
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Remove(self)
Remove the rbd device.
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Rename(self, new_id)
Rename this device.
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Attach(self)
Attach to an existing rbd device.
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string
_MapVolumeToBlockdev(self, unique_id)
Maps existing rbd volumes to block devices.
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Assemble(self)
Assemble the device.
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Shutdown(self)
Shutdown the device.
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_UnmapVolumeFromBlockdev(self, unique_id)
Unmaps the rbd device from the Volume it is mapped.
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Open(self, force=False)
Make the device ready for I/O.
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Close(self)
Notifies that the device will no longer be used for I/O.
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Grow(self, amount, dryrun, backingstore, excl_stor)
Grow the Volume.
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string
GetUserspaceAccessUri(self, hypervisor)
Generate KVM userspace URIs to be used as `-drive file` settings.
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Inherited from base.BlockDev: CombinedSyncStatus, GetActualDimensions, GetActualSize, GetActualSpindles, GetSyncStatus, PauseResumeSync, SetInfo, SetSyncParams, __repr__

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __setattr__, __sizeof__, __str__, __subclasshook__

Class Methods [hide private]
BlockDev
Create(cls, unique_id, children, size, spindles, params, excl_stor, dyn_params, *args)
Create a new rbd device.
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string or None
_VolumeToBlockdev(cls, pool, volume_name)
Do the 'volume name'-to-'rbd block device' resolving.
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Static Methods [hide private]
string or None
_ParseRbdShowmappedJson(output, volume_name)
Parse the json output of `rbd showmapped'.
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string or None
_ParseRbdShowmappedPlain(output, volume_name)
Parse the (plain / text) output of `rbd showmapped'.
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Properties [hide private]

Inherited from object: __class__

Method Details [hide private]

__init__(self, unique_id, children, size, params, dyn_params, *args)
(Constructor)

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Attaches to an rbd device.

Overrides: object.__init__

Create(cls, unique_id, children, size, spindles, params, excl_stor, dyn_params, *args)
Class Method

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Create a new rbd device.

Provision a new rbd volume inside a RADOS pool.

Parameters:
  • unique_id - unique identifier; the details depend on the actual device type
  • children - for hierarchical devices, the child devices
  • size - size in MiB
  • spindles - number of physical disk to dedicate to the device
  • params - device-specific options/parameters
  • excl_stor - whether exclusive_storage is active
  • dyn_params - dynamic parameters of the disk only valid for this node. As set by objects.Disk.UpdateDynamicDiskParams.
Returns: BlockDev
the created device, or None in case of an error
Overrides: base.BlockDev.Create

Remove(self)

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Remove the rbd device.

Overrides: base.BlockDev.Remove

Rename(self, new_id)

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Rename this device.

Overrides: base.BlockDev.Rename

Attach(self)

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Attach to an existing rbd device.

This method maps the rbd volume that matches our name with an rbd device and then attaches to this device.

Overrides: base.BlockDev.Attach

_MapVolumeToBlockdev(self, unique_id)

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Maps existing rbd volumes to block devices.

This method should be idempotent if the mapping already exists.

Returns: string
the block device path that corresponds to the volume

_VolumeToBlockdev(cls, pool, volume_name)
Class Method

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Do the 'volume name'-to-'rbd block device' resolving.

Parameters:
  • pool (string) - RADOS pool to use
  • volume_name (string) - the name of the volume whose device we search for
Returns: string or None
block device path if the volume is mapped, else None

_ParseRbdShowmappedJson(output, volume_name)
Static Method

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Parse the json output of `rbd showmapped'.

This method parses the json output of `rbd showmapped' and returns the rbd block device path (e.g. /dev/rbd0) that matches the given rbd volume.

Parameters:
  • output (string) - the json output of `rbd showmapped'
  • volume_name (string) - the name of the volume whose device we search for
Returns: string or None
block device path if the volume is mapped, else None

_ParseRbdShowmappedPlain(output, volume_name)
Static Method

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Parse the (plain / text) output of `rbd showmapped'.

This method parses the output of `rbd showmapped' and returns the rbd block device path (e.g. /dev/rbd0) that matches the given rbd volume.

Parameters:
  • output (string) - the plain text output of `rbd showmapped'
  • volume_name (string) - the name of the volume whose device we search for
Returns: string or None
block device path if the volume is mapped, else None

Assemble(self)

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Assemble the device.

Overrides: base.BlockDev.Assemble

Shutdown(self)

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Shutdown the device.

Overrides: base.BlockDev.Shutdown

_UnmapVolumeFromBlockdev(self, unique_id)

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Unmaps the rbd device from the Volume it is mapped.

Unmaps the rbd device from the Volume it was previously mapped to. This method should be idempotent if the Volume isn't mapped.

Open(self, force=False)

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Make the device ready for I/O.

Overrides: base.BlockDev.Open

Close(self)

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Notifies that the device will no longer be used for I/O.

Overrides: base.BlockDev.Close

Grow(self, amount, dryrun, backingstore, excl_stor)

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Grow the Volume.

Parameters:
  • amount (integer) - the amount (in mebibytes) to grow with
  • dryrun (boolean) - whether to execute the operation in simulation mode only, without actually increasing the size
Overrides: base.BlockDev.Grow

GetUserspaceAccessUri(self, hypervisor)

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Generate KVM userspace URIs to be used as `-drive file` settings.

Returns: string
userspace device URI
Raises:
Overrides: base.BlockDev.GetUserspaceAccessUri