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with write access by Mac OS 10.7.5 or higher, Windows 7 or higher, and Linux kernel
2.6.18 or higher. While you can change SUW HFS+ (MAC OS
EXTENDED) formatted volumes as Multi-user Write, NTFS is recommended. Setting
an HFS+ (MAC OS EXTENDED) volume to Multi-user Write requires that you install
the latest version of the
MediaFour MacDrive
software on the TerraBlock Server.
Logical Volumes
When creating a volume the Terrablock server creates the volume in logical pieces.
A logical volume may be no more than 1000GB. Thus larger volumes are
constructed with more logical pieces. Each logical volume has a second RAID or
Mirror piece unless the volume is unprotected. Expanding a volume creates new
logical volumes.
The logical volume limit on a server is 475 per drive group. The
logical volume count can be seen by launching SMDriveMonitor or
Dataverifier. Exceeding the logical volume limit may prevent you from
creating new volumes.
DynaRAID
The DynaRAID option within the ‘Create Volume’ window allows the system
Administrator to determine which protection scheme will be used on a per virtual
volume basis.
DynaRAID: Single TerraBlock Server
In a mirrored volume, data on one drive is protected by another drive or set
of drives. If an individual physical drive fails, there is a backup copy of the
information contained on the mirrored volume which is read from the
remaining drives. Mirrored volumes require available storage space that is
equal to the size of the volume. Mirrored data is self-contained on a single
TerraBlock Server.
In a RAID5 Parity volume, data is compressed and saved as parity
information. The RAID5 compression algorithm reduces the space required for
protection of data to about 9% of the total volume size. In the event of an
individual physical drive failure, the data is read in real-time from the parity
information contained on the remaining drives. RAID5 data is self-contained
on a single TerraBlock Server.
In an unprotected volume, there is no RAID5 or mirroring protection to back
up the data contained on the volume. Unprotected volumes are not
recoverable in the case of an individual physical drive failure. If an individual
physical drive failure occurs, all data residing on unprotected volumes will be
lost. This data will need to be re-ingested. Because unprotected volumes
contain no DynaRAID protection, no additional storage space is required.
DynaRAID: Multiple TerraBlock Servers or Facilis TX16 Expansion Chassis
DynaRAID volume protection scheme also allows RAID5 Parity data to be striped or
mirrored across multiple TerraBlock Servers or
Facilis TX16 Expansion Chassis
’.
