8.6.7. Creating a File Storage Pool

A file storage pool draws its storage capacity from a logical volume storage pool. A logical volume storage pool must therefore always be specified, when creating a file storage pool. The command for creating a file storage pool is the same as for a logical volume storage pool, “vios mksp“, only the arguments differ:

$ vios mksp ms05-vio1 filepool rootvg 10g

We have specified the always existing logical volume storage pool rootvg. In practice, however, this is usually not a good idea and a logical volume storage pool created specifically for storage provisioning should be specified. The required capacity for the file storage pool to be created must be specified.

The newly created file storage pool appears immediately in the list of storage pools:

$ vios lssp ms05-vio1
POOL      TYPE    SIZE       FREE       ALLOC      BDS
rootvg    LVPOOL  558.00 GB   58.00 GB  512.00 MB  0
filepool  FBPOOL    9.96 GB    9.96 GB  512.00 MB  0

The type of storage pool can be clearly seen in the TYPE column. Technically, a logical volume is created in the specified logical volume storage pool (here rootvg). The logical volume is given the name filepool specified in the command. The virtual I/O server then creates a file system on the logical volume and mounts the new file system under the path /var/vio/storagepools/filepool.

The administration of backing devices (creation, mapping, unmapping, extending, removing) works exactly as described above for logical volume storage pools. The only difference is that the backing devices are no longer logical volumes, but are created as files in the file system. Here is a quick example:

$ vios mkbdsp ms05-vio1 filepool bd001 1g vhost0

The command is absolutely identical to the commands used above!

Also, when listing the backing devices in a storage pool, there is no difference to the case of a logical volume storage pool:

$ vios lsbdsp ms05-vio1 filepool
bd001     1.00 GB  vtscsi5  vhost0

The backing device bd001 has a size of 1 GB and is assigned to the adapter vhost0 via the virtual target device vtscsi5.