|
|
|
|
|
Before creating a volume, you may wish to check whether there is sufficient storage available.
You can use the following command to determine the maximum size of a volume with a given capability that you can create in the data storage pool of a disk group:
# vxassist [-g diskgroup] [-P storage_pool] [-b] maxsize \
[storage_specification] [attribute=value ...]
Specify the -b option if you want to run this command in the background. Otherwise, it will block until it has completed its calculation of the maximum volume size.
The storage that is available for allocation is based on the setting of the AutoGrow policy on a storage pool. If the value of this policy is set to diskgroup and not to pool, all suitable disks in the disk group are used in the calculation. You can use the -P option to specify that only storage from the specified pool is to be considered.
For example, the following command returns the maximum possible size of a mirrored volume with three mirrors that can be created from all the available free storage:
# vxassist -g mydg -P mypool maxsize layout=mirror nmir=3
The following command is equivalent if the DataMirroring capability is specified:
# vxassist -g mydg -P mypool maxsize \
capability='DataMirroring(nmirs=3)'
The following example checks for the maximum volume size that can be created using prefabricated mirrors of a specified vendor type:
# vxassist -g peakdg -P peakpool maxsize \
volume_template=PrefabricatedDataMirroring \
rules='confineto "VendorName"="ACME"'
The maximum size of a VxVM volume that you can create is 256 TB.