LaCie 2big Quadra RAID Modes

This section will help you decide which RAID mode is right for your application.

Fast (RAID 0)

The 2big Quadra is pre-configured in RAID 0, the fastest RAID mode. Requiring at least 2 drives, RAID 0 stripes data onto each disk. The available capacities of each disk are added together so that one logical volume mounts on the computer. If one physical disk in the array fails, the data of all disks becomes inaccessible because parts of the data have been written to all disks.

Applications

RAID 0 is ideal for users who need maximum speed and capacity. Video editors working with very large files may use RAID 0 when editing multiple streams of video for optimal playback performance. While a RAID 0 array is suited for actively working with files (editing video, for example), users interested in a higher level of security should use RAID1.

Big (Concatenation)

When disks are concatenated, their capacities are combined and data is written to the primary disk in the array until is it full, and then to successive disks. Concatenation provides no performance advantage or added measure of data safety. It is simply a method of combining more than one physical disk into one volume for greater overall capacity. Concatenation allows full use of the capacity of all disks in the array, but users interested in a higher level of protection should use RAID1.

Safe (RAID 1)

In Safe mode (RAID 1), the two physical disks are mirrored together so that one single logical volume mounts on the desktop. All data is saved simultaneously on each disk (the available capacity cannot exceed the available capacity of the lowest-capacity single disk). If one physical disk fails, the data is available immediately on the second disk. No data is lost if one disk fails.

Applications

• Maximum data safety
• Safe reduces the total available capacity by 50% because two copies of the data are saved.

Mixed (RAID 1 and RAID 0)

In Mixed mode, the two physical disks are combined so that two logical volumes mount simultaneously on the desktop:

• One Safe volume (RAID 1) where data is automatically mirrored on each physical disk. This volume uses 50% of the available capacity of each disk (the available capacity cannot exceed 50% of the lowest-capacity single disk).

Note: If one physical disk fails, the data of the SAFE volume is available on the second disk. Only 25% of full capacity is protected by mirroring. In this case, data on the Fast (RAID 0) volume will be lost.

• One Fast volume (RAID 0) enables the user to work with the high speed of RAID 0.

Applications

• Provides two volumes for different data security needs.
• Only 75% of total formatted capacity is available due to mirroring on the Safe volume.