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+.. _ceph-volume-lvm-batch:
+
+``batch``
+===========
+The subcommand allows to create multiple OSDs at the same time given
+an input of devices. The ``batch`` subcommand is closely related to
+drive-groups. One individual drive group specification translates to a single
+``batch`` invocation.
+
+The subcommand is based to :ref:`ceph-volume-lvm-create`, and will use the very
+same code path. All ``batch`` does is to calculate the appropriate sizes of all
+volumes and skip over already created volumes.
+
+All the features that ``ceph-volume lvm create`` supports, like ``dmcrypt``,
+avoiding ``systemd`` units from starting, defining bluestore,
+is supported.
+
+
+.. _ceph-volume-lvm-batch_auto:
+
+Automatic sorting of disks
+--------------------------
+If ``batch`` receives only a single list of data devices and other options are
+passed , ``ceph-volume`` will auto-sort disks by its rotational
+property and use non-rotating disks for ``block.db`` or ``journal`` depending
+on the objectstore used. If all devices are to be used for standalone OSDs,
+no matter if rotating or solid state, pass ``--no-auto``.
+For example assuming :term:`bluestore` is used and ``--no-auto`` is not passed,
+the deprecated behavior would deploy the following, depending on the devices
+passed:
+
+#. Devices are all spinning HDDs: 1 OSD is created per device
+#. Devices are all SSDs: 2 OSDs are created per device
+#. Devices are a mix of HDDs and SSDs: data is placed on the spinning device,
+ the ``block.db`` is created on the SSD, as large as possible.
+
+.. note:: Although operations in ``ceph-volume lvm create`` allow usage of
+ ``block.wal`` it isn't supported with the ``auto`` behavior.
+
+This default auto-sorting behavior is now DEPRECATED and will be changed in future releases.
+Instead devices are not automatically sorted unless the ``--auto`` option is passed
+
+It is recommended to make use of the explicit device lists for ``block.db``,
+ ``block.wal`` and ``journal``.
+
+.. _ceph-volume-lvm-batch_bluestore:
+
+Reporting
+=========
+By default ``batch`` will print a report of the computed OSD layout and ask the
+user to confirm. This can be overridden by passing ``--yes``.
+
+If one wants to try out several invocations with being asked to deploy
+``--report`` can be passed. ``ceph-volume`` will exit after printing the report.
+
+Consider the following invocation::
+
+ $ ceph-volume lvm batch --report /dev/sdb /dev/sdc /dev/sdd --db-devices /dev/nvme0n1
+
+This will deploy three OSDs with external ``db`` and ``wal`` volumes on
+an NVME device.
+
+Pretty reporting
+----------------
+
+The ``pretty`` report format (the default) would
+look like this::
+
+ $ ceph-volume lvm batch --report /dev/sdb /dev/sdc /dev/sdd --db-devices /dev/nvme0n1
+ --> passed data devices: 3 physical, 0 LVM
+ --> relative data size: 1.0
+ --> passed block_db devices: 1 physical, 0 LVM
+
+ Total OSDs: 3
+
+ Type Path LV Size % of device
+ ----------------------------------------------------------------------------------------------------
+ data /dev/sdb 300.00 GB 100.00%
+ block_db /dev/nvme0n1 66.67 GB 33.33%
+ ----------------------------------------------------------------------------------------------------
+ data /dev/sdc 300.00 GB 100.00%
+ block_db /dev/nvme0n1 66.67 GB 33.33%
+ ----------------------------------------------------------------------------------------------------
+ data /dev/sdd 300.00 GB 100.00%
+ block_db /dev/nvme0n1 66.67 GB 33.33%
+
+
+JSON reporting
+--------------
+
+Reporting can produce a structured output with ``--format json`` or
+``--format json-pretty``::
+
+ $ ceph-volume lvm batch --report --format json-pretty /dev/sdb /dev/sdc /dev/sdd --db-devices /dev/nvme0n1
+ --> passed data devices: 3 physical, 0 LVM
+ --> relative data size: 1.0
+ --> passed block_db devices: 1 physical, 0 LVM
+ [
+ {
+ "block_db": "/dev/nvme0n1",
+ "block_db_size": "66.67 GB",
+ "data": "/dev/sdb",
+ "data_size": "300.00 GB",
+ "encryption": "None"
+ },
+ {
+ "block_db": "/dev/nvme0n1",
+ "block_db_size": "66.67 GB",
+ "data": "/dev/sdc",
+ "data_size": "300.00 GB",
+ "encryption": "None"
+ },
+ {
+ "block_db": "/dev/nvme0n1",
+ "block_db_size": "66.67 GB",
+ "data": "/dev/sdd",
+ "data_size": "300.00 GB",
+ "encryption": "None"
+ }
+ ]
+
+Sizing
+======
+When no sizing arguments are passed, `ceph-volume` will derive the sizing from
+the passed device lists (or the sorted lists when using the automatic sorting).
+`ceph-volume batch` will attempt to fully utilize a device's available capacity.
+Relying on automatic sizing is recommended.
+
+If one requires a different sizing policy for wal, db or journal devices,
+`ceph-volume` offers implicit and explicit sizing rules.
+
+Implicit sizing
+---------------
+Scenarios in which either devices are under-committed or not all data devices are
+currently ready for use (due to a broken disk for example), one can still rely
+on `ceph-volume` automatic sizing.
+Users can provide hints to `ceph-volume` as to how many data devices should have
+their external volumes on a set of fast devices. These options are:
+
+* ``--block-db-slots``
+* ``--block-wal-slots``
+* ``--journal-slots``
+
+For example, consider an OSD host that is supposed to contain 5 data devices and
+one device for wal/db volumes. However, one data device is currently broken and
+is being replaced. Instead of calculating the explicit sizes for the wal/db
+volume, one can simply call::
+
+ $ ceph-volume lvm batch --report /dev/sdb /dev/sdc /dev/sdd /dev/sde --db-devices /dev/nvme0n1 --block-db-slots 5
+
+Explicit sizing
+---------------
+It is also possible to provide explicit sizes to `ceph-volume` via the arguments
+
+* ``--block-db-size``
+* ``--block-wal-size``
+* ``--journal-size``
+
+`ceph-volume` will try to satisfy the requested sizes given the passed disks. If
+this is not possible, no OSDs will be deployed.
+
+
+Idempotency and disk replacements
+=================================
+`ceph-volume lvm batch` intends to be idempotent, i.e. calling the same command
+repeatedly must result in the same outcome. For example calling::
+
+ $ ceph-volume lvm batch --report /dev/sdb /dev/sdc /dev/sdd --db-devices /dev/nvme0n1
+
+will result in three deployed OSDs (if all disks were available). Calling this
+command again, you will still end up with three OSDs and ceph-volume will exit
+with return code 0.
+
+Suppose /dev/sdc goes bad and needs to be replaced. After destroying the OSD and
+replacing the hardware, you can again call the same command and `ceph-volume`
+will detect that only two out of the three wanted OSDs are setup and re-create
+the missing OSD.
+
+This idempotency notion is tightly coupled to and extensively used by :ref:`drivegroups`.