Administrator Guide

Local file system symbolic links are available in NTFS starting with Windows Vista and Windows Server 2008, but the symbolic links over
SMB are available only with SMB2.
Limitations on Using Symbolic Links
When using symbolic links, note the following limitations:
• SMB1, FTP, and NFS do not support symbolic links.
• Symbolic links are limited to 2,000 bytes.
• User and directory quotas do not apply to symbolic links.
• FluidFS space counting does not count symbolic link data as regular file data.
• Symbolic links are not followed when accessed from snapshot view. They appear as regular files or folders.
• If a relative symbolic link was moved to another location, it might become invalid.
• Cloning SMB symbolic links is not supported.
File Access
Symbolic links are enabled by default. You cannot configure symbolic links in FluidFS, but you can access them using the following
Microsoft tools:
• mklink – Basic utility used to create both symbolic and hard links (hard links are not supported over SMB, but locally only)
• fsutil – File system utility that enables working with reparse points and modifying symbolic links policy
For more information about symbolic links, go to https://msdn.microsoft.com/en-us/library/windows/desktop/
aa365680%28v=vs.85%29.aspx.
Managing Quota Rules
Quota rules allow you to control the amount of NAS volume space that a user or group can utilize. Quotas are configured on a per NAS
volume basis.
When a user reaches a specified portion of the quota size (soft quota limit), an alert is sent to the storage administrator. When the
maximum quota size (hard quota limit) is reached, users cannot write data to the SMB shares and NFS exports on the NAS volume, but
no alert is generated.
About Data Reduction
The FluidFS cluster supports two types of data reduction:
• Data deduplication – Uses algorithms to eliminate redundant data, leaving only one copy of the data to be stored. The FluidFS
cluster uses variable-size block level deduplication as opposed to file level deduplication or fixed-size block level deduplication.
• Data compression – Uses algorithms to reduce the size of stored data.
When using data reduction, note the following limitations:
• The minimum file size to be considered for data reduction processing is 65 KB.
• Because quotas are based on logical rather than physical space consumption, data reduction does not affect quota calculations.
• If you disable data reduction, data remains in its reduced state during subsequent read operations by default. You can enable
rehydrate-on-read when disabling data reduction, which causes a rehydration (the reversal of data reduction) of data on subsequent
read operations. You cannot rehydrate an entire NAS volume in the background, although you could accomplish this task by reading
the entire NAS volume.
• Cross-volume deduplication is not supported at this time.
• Data reduction does not support base clone and cloned volumes.
Table 15. Data Reduction Enhancements in FluidFS v6.0 or later
FluidFS v6.0 or later FluidFS v5.0 or earlier
Data reduction is enabled on a per-NAS-cluster basis. Data reduction is enabled on a per-NAS-volume basis.
Data reduction supports deduplication of files that are created or
reside on different domains.
Data reduction is applied per NAS controller, that is, the same
chunks of data that are owned by the different NAS controllers are
not considered duplicates.
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