Administrator Guide

Using Symbolic Links
A symbolic link is a special type of file that contains a reference to another file or directory in the form of an absolute or relative
path and that affects path name resolution. Symbolic links operate transparently for most operations: programs that read or
write to files named by a symbolic link behave as if operating directly on the target file. The symbolic link contains a text string
that is automatically interpreted and followed by the operating system as a path to another file or directory.
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.
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FluidFS Administration