Quantum 3.5.2 manual Storage Disk Deduplication

Chapter 10 Managing Storage Disks

Storage Disk Deduplication

•Use complete and physically dedicated file systems (snfs, local, nfs, or other,) for storage disk data, not shared file systems or file systems with linked directories.

•If your file system includes storage disks and you accidentally fill it with unrelated user data (i.e., non-storage disk data,) call the Quantum Technical Assistance Center and ask for a procedure to clean up and transcribe data.

Storage Disk Deduplication

StorNext supports storage disk deduplication only on non-managed file systems. Deduplication frees disk space by eliminating redundant data. The deduplication process does not retain duplicate data, so there is only one copy of the data to be stored. (Indexing of all data is retained in case that data is required later.) The main benefit of deduplication is that it reduces storage capacity requirements because only unique data is stored. Without deduplication, offline copies of a file consume as much disk space as the original file.

When you create a new storage disk, you will be given the option of enabling deduplication. StorNext refers to a storage disk with deduplication enabled as a dedup SDISK. If your system configuration consists only of storage disks, the same rules that apply to storage disks apply to deduplication-enabled storage disks. For example, in a storage disk-only configuration the first storage disk must always use file copy 1.

You can create up to 4 dedup sdisks. (You can have a total of 16 storage disks, of which 4 can be dedup sdisks.)

You must have a minimum of 2GB of RAM for each dedup sdisk you plan to use.

Note: The 2GB of RAM per dedup sdisk is in addition to the memory required for StorNext.

At this time storage disk deduplication is supported only on 32 bit and 64 bit Linux platforms.

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