Create Storage Pool

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A storage pool is a combination of one or more disks combined together into a flexible abstract layer from which you can provision both storage volumes (LUNs) and network shares.

Selecting the RAID Type

Storage pools have support for software RAID levels including RAID0, RAID1/10, RAID5/50/Z1, RAID6/60/Z2, and RAIDZ3. QuantaStor storage pools default to using the ZFS filesystem and have the added advantage that you can expand them by adding more storage to them at any time. Note that one cannot shrink storage pools it is important to take care when expanding a given pool.

Selecting Disks

Storage pools typically are formed from disk drives which are multipath connected to two HBAs on two separate servers so that the pool can be made highly-available. When selecting multiple disks be sure to select disks of the same size. If one combines disks of different sizes it can compromise performance or make it less predictable. If multiple disks of differing sizes are combined together within a VDEV (group of disks) the lowest common denominator is used leaving wasted space. It is also recommended that you use disks all from the same manufacturer rather than mixing drives which may have different performance characteristics.

Selecting an I/O Profile

I/O profiles allow you to adjust some settings like block size and read-ahead amounts for the storage pool to tune the pool for specific workloads. For SSD based storage pools be sure to change the setting to 'Default SSD' which will boost IOPS.

(XFS ONLY) Write Cache Optimizations

For Ceph based storage configurations XFS based pools are used. One may enable write cache optimizations on the underlying XFS pools when the storage is from a hardware RAID controller with a flash cache or battery backup unit which protects the write cache in the controller.

Compression

Compression is enabled by default and uses very little CPU power and will boost performance as it can greatly reduce the amount of data written and read from disk. Typical performance increases from enabling compression is 10%-20% and will make use of multiple processor cores.

Search/Reset Buttons

You may refine the Disks displayed by entering search criteria and pressing Search button to reduce the volumes displayed. Multiple comma separated values may be used to further refine the volumes displayed. To see all the volumes press the Reset button.

Interpreting Hardware Information

For disks attached to some HBA cards, the "Hardware" column contains information about the Hardware Disk physical location, in the form of "(<HBA-PCI-Addr>:<Enclosure-Number>:<Slot-Number>)". For example:"3:8:12", or "81:252:11". The administrator can sort the disk table on this field, and using this information can make an informed selection of disks based on requirements for colocation, redundancy, etc.

Navigation: Storage Management --> Storage Pools --> Storage Pool --> Create (toolbar)

Create Stor Pool Gerneral.jpg


Create Storage Pool Settings.png


For additional information see Creating Storage Pools


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