mirror of
https://github.com/ceph/ceph
synced 2024-12-26 21:43:10 +00:00
02c2ef8c3b
Give the Powershell command that identifies the Windows drive letter when partitioning a new RBD image. Signed-off-by: Ken Dreyer <kdreyer@redhat.com>
189 lines
7.1 KiB
ReStructuredText
189 lines
7.1 KiB
ReStructuredText
==============
|
|
RBD on Windows
|
|
==============
|
|
|
|
The ``rbd`` command can be used to create, remove, import, export, map or
|
|
unmap images exactly like it would on Linux. Make sure to check the
|
|
`RBD basic commands`_ guide.
|
|
|
|
``librbd.dll`` is also available for applications that can natively use Ceph.
|
|
|
|
Please check the `installation guide`_ to get started.
|
|
|
|
Windows service
|
|
===============
|
|
On Windows, ``rbd-wnbd`` daemons are managed by a centralized service. This allows
|
|
decoupling the daemons from the Windows session from which they originate. At
|
|
the same time, the service is responsible of recreating persistent mappings,
|
|
usually when the host boots.
|
|
|
|
Note that only one such service may run per host.
|
|
|
|
By default, all image mappings are persistent. Non-persistent mappings can be
|
|
requested using the ``-onon-persistent`` ``rbd`` flag.
|
|
|
|
Persistent mappings are recreated when the service starts, unless explicitly
|
|
unmapped. The service disconnects the mappings when being stopped. This also
|
|
allows adjusting the Windows service start order so that RBD images can be
|
|
mapped before starting services that may depend on it, such as VMMS.
|
|
|
|
In order to be able to reconnect the images, ``rbd-wnbd`` stores mapping
|
|
information in the Windows registry at the following location:
|
|
``SYSTEM\CurrentControlSet\Services\rbd-wnbd``.
|
|
|
|
The following command can be used to configure the service. Please update
|
|
the ``rbd-wnbd.exe`` path accordingly::
|
|
|
|
New-Service -Name "ceph-rbd" `
|
|
-Description "Ceph RBD Mapping Service" `
|
|
-BinaryPathName "c:\ceph\rbd-wnbd.exe service" `
|
|
-StartupType Automatic
|
|
|
|
Note that the Ceph MSI installer takes care of creating the ``ceph-rbd``
|
|
Windows service.
|
|
|
|
Usage
|
|
=====
|
|
|
|
Integration
|
|
-----------
|
|
|
|
RBD images can be exposed to the OS and host Windows partitions or they can be
|
|
attached to Hyper-V VMs in the same way as iSCSI disks.
|
|
|
|
Starting with Openstack Wallaby, the Nova Hyper-V driver can attach RBD Cinder
|
|
volumes to Hyper-V VMs.
|
|
|
|
Mapping images
|
|
--------------
|
|
|
|
The workflow and CLI is similar to the Linux counterpart, with a few
|
|
notable differences:
|
|
|
|
* device paths cannot be requested. The disk number and path will be picked by
|
|
Windows. If a device path is provided by the used when mapping an image, it
|
|
will be used as an identifier, which can also be used when unmapping the
|
|
image.
|
|
* the ``show`` command was added, which describes a specific mapping.
|
|
This can be used for retrieving the disk path.
|
|
* the ``service`` command was added, allowing ``rbd-wnbd`` to run as a Windows service.
|
|
All mappings are by default persistent, being recreated when the service
|
|
stops, unless explicitly unmapped. The service disconnects the mappings
|
|
when being stopped.
|
|
* the ``list`` command also includes a ``status`` column.
|
|
|
|
The purpose of the ``service`` mode is to ensure that mappings survive reboots
|
|
and that the Windows service start order can be adjusted so that RBD images can
|
|
be mapped before starting services that may depend on it, such as VMMS.
|
|
|
|
The mapped images can either be consumed by the host directly or exposed to
|
|
Hyper-V VMs.
|
|
|
|
Hyper-V VM disks
|
|
----------------
|
|
|
|
The following sample imports an RBD image and boots a Hyper-V VM using it::
|
|
|
|
# Feel free to use any other image. This one is convenient to use for
|
|
# testing purposes because it's very small (~15MB) and the login prompt
|
|
# prints the pre-configured password.
|
|
wget http://download.cirros-cloud.net/0.5.1/cirros-0.5.1-x86_64-disk.img `
|
|
-OutFile cirros-0.5.1-x86_64-disk.img
|
|
|
|
# We'll need to make sure that the imported images are raw (so no qcow2 or vhdx).
|
|
# You may get qemu-img from https://cloudbase.it/qemu-img-windows/
|
|
# You can add the extracted location to $env:Path or update the path accordingly.
|
|
qemu-img convert -O raw cirros-0.5.1-x86_64-disk.img cirros-0.5.1-x86_64-disk.raw
|
|
|
|
rbd import cirros-0.5.1-x86_64-disk.raw
|
|
# Let's give it a hefty 100MB size.
|
|
rbd resize cirros-0.5.1-x86_64-disk.raw --size=100MB
|
|
|
|
rbd device map cirros-0.5.1-x86_64-disk.raw
|
|
|
|
# Let's have a look at the mappings.
|
|
rbd device list
|
|
Get-Disk
|
|
|
|
$mappingJson = rbd-wnbd show cirros-0.5.1-x86_64-disk.raw --format=json
|
|
$mappingJson = $mappingJson | ConvertFrom-Json
|
|
|
|
$diskNumber = $mappingJson.disk_number
|
|
|
|
New-VM -VMName BootFromRBD -MemoryStartupBytes 512MB
|
|
# The disk must be turned offline before it can be passed to Hyper-V VMs
|
|
Set-Disk -Number $diskNumber -IsOffline $true
|
|
Add-VMHardDiskDrive -VMName BootFromRBD -DiskNumber $diskNumber
|
|
Start-VM -VMName BootFromRBD
|
|
|
|
Windows partitions
|
|
------------------
|
|
|
|
The following sample creates an empty RBD image, attaches it to the host and
|
|
initializes a partition::
|
|
|
|
rbd create blank_image --size=1G
|
|
rbd device map blank_image -onon-persistent
|
|
|
|
$mappingJson = rbd-wnbd show blank_image --format=json
|
|
$mappingJson = $mappingJson | ConvertFrom-Json
|
|
|
|
$diskNumber = $mappingJson.disk_number
|
|
|
|
# The disk must be online before creating or accessing partitions.
|
|
Set-Disk -Number $diskNumber -IsOffline $false
|
|
|
|
# Initialize the disk, partition it and create a filesystem.
|
|
Get-Disk -Number $diskNumber | `
|
|
Initialize-Disk -PassThru | `
|
|
New-Partition -AssignDriveLetter -UseMaximumSize | `
|
|
Format-Volume -Force -Confirm:$false
|
|
|
|
# Show the partition letter (for example, "D:" or "F:"):
|
|
(Get-Partition -DiskNumber $diskNumber).DriveLetter
|
|
|
|
|
|
Limitations
|
|
-----------
|
|
|
|
CSV support
|
|
~~~~~~~~~~~
|
|
|
|
At the moment, the Microsoft Failover Cluster can't use WNBD disks as
|
|
Cluster Shared Volumes (CSVs) underlying storage. The main reason is that
|
|
``WNBD`` and ``rbd-wnbd`` don't support the *SCSI Persistent Reservations*
|
|
feature yet.
|
|
|
|
Hyper-V disk addressing
|
|
~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
.. warning::
|
|
Hyper-V identifies passthrough VM disks by number instead of SCSI ID, although
|
|
the disk number can change across host reboots. This means that the VMs can end
|
|
up using incorrect disks after rebooting the host, which is an important
|
|
security concern. This issue also affects iSCSI and Fibre Channel disks.
|
|
|
|
There are a few possible ways of avoiding this Hyper-V limitation:
|
|
|
|
* use an NTFS/ReFS partition to store VHDX image files instead of directly
|
|
attaching the RBD image. This may slightly impact the IO performance.
|
|
* use the Hyper-V ``AutomaticStartAction`` setting to prevent the VMs from
|
|
booting with the incorrect disks and have a script that updates VM disks
|
|
attachments before powering them back on. The ``ElementName`` field of the
|
|
`Msvm_StorageAllocationSettingData`_ `WMI`_ class may be used to label VM
|
|
disk attachments.
|
|
* use the Openstack Hyper-V driver, which automatically refreshes the VM disk
|
|
attachments before powering them back on.
|
|
|
|
Troubleshooting
|
|
===============
|
|
|
|
Please consult the `Windows troubleshooting`_ page.
|
|
|
|
.. _Windows troubleshooting: ../../install/windows-troubleshooting
|
|
.. _installation guide: ../../install/windows-install
|
|
.. _RBD basic commands: ../rados-rbd-cmds
|
|
.. _WNBD driver: https://github.com/cloudbase/wnbd
|
|
.. _Msvm_StorageAllocationSettingData: https://docs.microsoft.com/en-us/windows/win32/hyperv_v2/msvm-storageallocationsettingdata
|
|
.. _WMI: https://docs.microsoft.com/en-us/windows/win32/wmisdk/wmi-start-page
|