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Dell PowerVault ME4 Series Storage System CLI Guide

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create volume


Description	Creates a volume in a linear disk group or virtual pool. You must specify a size for the volume. You can create the volume unmapped or set its default mapping. Default mapping settings apply to all hosts. However, a default mapping must be removed to apply an explicit mapping between a host and the volume. You can change the mapping by using the map volume and unmap volume commands. By default, the create volume command will not map the created volume. CAUTION:Using a default mapping for a volume will allow multiple hosts to access the volume. To avoid multiple hosts mounting the volume and causing corruption, the hosts must be cooperatively managed, such as by using cluster software. Volume sizes are aligned to 4.2 MB (4 MiB) boundaries. When a volume is created or expanded, if the resulting size would be less than 4.2 MB it will be increased to 4.2 MB; if the resulting size would be greater than 4.2 MB it will be decreased to the nearest 4.2 MB boundary. To create multiple volumes at once, use the create volume-set command. NOTE:For virtual storage, you cannot add a volume to a volume group that is in a replication set. For virtual storage, you can set the retention priority for snapshots of the volume. If automatic deletion of snapshots is enabled, the system uses the retention priority of snapshots to determine which, if any, snapshots to delete. Snapshots are considered to be eligible for deletion if they have any retention priority other than never-delete. Eligible snapshots are considered for deletion by priority and age. The oldest, lowest priority snapshots are deleted first. Snapshots that are mapped or are not leaves of a volume’s snapshot tree are not eligible for automatic deletion.
Minimum role	manage
Syntax	create volume [access read-write\|rw\|read-only\|ro\|no-access] [large-virtual-extents enabled\|disabled\|on\|off] [lun `LUN`] [pool `pool`] [ports `ports`] [reserve `size`[B\|KB\|MB\|GB\|TB\|KiB\|MiB\|GiB\|TiB]] size `size`[B\|KB\|MB\|GB\|TB\|KiB\|MiB\|GiB\|TiB] [snapshot-retention-priority never-delete\|high\|medium\|low] [tier-affinity no-affinity\|archive\|performance] vdisk `vdisk` [volume-group `volume-group`] `name`
Parameters	access read-write\|rw\|read-only\|ro\|no-access Optional. The access permission to use for the mapping: read-write (rw), read-only (ro), or no-access. If no-access is specified, the volume is not mapped. The default is read-write Optional. For a virtual volume, this sets whether the system will try to allocate pages in a sequentially optimized way to reduce I/O latency in SSD applications and improve performance. disabled or off: Optimized page allocation is disabled. This is the defaullarge-virtual-extents enabled\|disabled\|on\|offt. enabled or on: Optimized page allocation is enabled. lun `LUN` Optional if the access parameter is set to no-access. Specifies the LUN to assign to the mapping on all ports. pool `pool` Optional for linear volumes. Required for virtual volumes. The name or serial number of the pool in which to create the volume. ports `ports` Optional. The ports through which the host can access the volume. All specified ports must be the same type (FC, for example). For port syntax, see Command syntax. If this parameter is omitted, all ports are selected. reserve `size`[B\|KB\|MB\|GB\|TB\|KiB\|MiB\|GiB\|TiB] Optional. Linear storage only. Specifies the size of the snap pool to create in the disk group. The unit is optional (B represents bytes). If base 2 is in use, whether you specify a base-2 or base-10 unit, the resulting size will be in base 2. If no unit is specified, the default is 512-byte blocks. If this parameter is omitted, the size will be either 20% of the volume size or 5.37 GB, whichever is larger. The recommended minimum size for a snap pool is 50 size `size`[B\|KB\|MB\|GB\|TB\|KiB\|MiB\|GiB\|TiB] Sets the volume size. The unit is optional (B represents bytes). If base 2 is in use, whether you specify a base-2 or base-10 unit, the resulting size will be in base 2. If no unit is specified, the default is 512-byte blocks. A value less than 4.2 MB (4 MiB) will be increased to that size. A value greater than 4 MB will be decreased to the nearest 4 MB boundary. The maximum size of a virtual volume is 140 TB (128 TiB). The maximum size of a linear volume is equal to the maximum size limit of the disk group. If overcommit is enabled, the size can exceed the physical capacity of the storage pool. To see whether overcommit is enabled, use the show pools command. When the overcommit feature is disabled, the host does not lose read or write access to the pool volumes when the pool reaches or exceeds the high threshold value. When the overcommit feature is enabled, the storage system sends the data protect sense key Add, Sense: Space allocation failed write protect to the host when the pool reaches or exceeds the high threshold value. If the host is rebooted after the pool reaches or exceeds the high threshold value, the host loses read and write access to the pool volumes. The only way to regain read and write access to the pool volumes is to add more storage to the pool. snapshot-retention-priority never-delete\|high\|medium\|low Optional. For virtual storage, this specifies the retention priority for snapshots of the volume. never-delete: Snapshots will never be deleted. high: Snapshots may be deleted after all eligible medium-priority snapshots have been deleted. medium: Snapshots may be deleted after all eligible low-priority snapshots have been deleted. This is the default. low: Snapshots may be deleted. tier-affinity no-affinity\|archive\|performance Optional. For virtual storage, this specifies how to tune the tier-migration algorithm for the volume: no-affinity: This setting uses the highest available performing tiers first and only uses the Archive tier when space is exhausted in the other tiers. Volume data will swap into higher performing tiers based on frequency of access and tier space availability. This is the default archive: This setting prioritizes the volume data to the least performing tier available. Volume data can move to higher performing tiers based on frequency of access and available space in the tiers. performance: This setting prioritizes volume data to the higher performing tiers. If no space is available, lower performing tier space is used. Performance affinity volume data will swap into higher tiers based upon frequency of access or when space is made available. vdisk `vdisk` Optional; required for linear volumes. The name or serial number of the linear disk group in which to create the volume. A name that includes a space must be enclosed in double quotes. volume-group `volume-group` Optional. The name of a volume group to which to add the volume. A name that includes a space must be enclosed in double quotes. If the group does not exist, it will be created. `name` A name for the new volume. The name must be unique system-wide. Input rules: The value is case sensitive. The value can have a maximum of 32 bytes. The value can include spaces and printable UTF-8 characters except: " , . < \ A value that includes a space must be enclosed in double quotes.
Examples	Create the 20-GB volume V1 in disk group VD1, and map it to ports A1 and B1 using LUN 5. # create volume vdisk VD1 size 20GB ports a1,b1 lun 5 V1 Create a 100-GB standard volume named MyVolume in pool A, map it to use LUN 5 with read-write access through port 1 in each controller, add it to volume group MyGroup, and tune tier-migration for performance. # create volume MyVolume pool A size 100GB access rw lun 5 ports 1 volume-group MyGroup tier-affinity performance Create a 20-GB standard volume named Secrets in storage pool A, and map it to use LUN 333 with read-only access through all ports. # create volume Secrets pool A size 20GB lun 333 access read-only Create volume Vol1 with snapshot retention priority high. # create volume snapshot-retention-priority high Vol1
See also	create volume-set delete volumes set volume show pools show ports show vdisks show volume-groups show volumes