HP ProLiant ML310 G3 Storage Server - Manual (Page 42)

If defragmenting volumes on which shadow copies are enabled, use a cluster (or allocation unit) size of
16 KB or larger during the format. Otherwise defragmentation registers as a change by the Shadow
Copy process. This increase in the number of changes forces Shadow Copy to delete snapshots as
the limit for the cache file is reached.
CAUTION:
Allocation unit size cannot be altered without reformatting the drive. Data on a reformatted drive
cannot be recovered.
For more information about disk defragmentation, read the online help.
Disk quotas
Disk quotas track and control disk space use in volumes.
NOTE:
To limit the size of a folder or share, see " Directory quotas " on page 65 .
Configure the volumes on the server to perform the following tasks:
• Prevent further disk space use and log an event when a user exceeds a specified disk space limit.
• Log an event when a user exceeds a specified disk space warning level.
When enabling disk quotas, it is possible to set both the disk quota limit and the disk quota warning
level. The disk quota limit specifies the amount of disk space a user is allowed to use. The warning level
specifies the point at which a user is nearing his or her quota limit. For example, a user's disk quota limit
can be set to 50 megabytes (MB), and the disk quota warning level to 45 MB. In this case, the user
can store no more than 50 MB on the volume. If the user stores more than 45 MB on the volume, the
disk quota system logs a system event.
In addition, it is possible to specify that users can exceed their quota limit. Enabling quotas and not
limiting disk space use is useful to still allow users access to a volume, but track disk space use on a
per-user basis. It is also possible to specify whether or not to log an event when users exceed either their
quota warning level or their quota limit.
When enabling disk quotas for a volume, volume usage is automatically tracked from that point forward,
but existing volume users have no disk quotas applied to them. Apply disk quotas to existing volume
users by adding new quota entries on the Quota Entries page.
NOTE:
When enabling disk quotas on a volume, any users with write access to the volume who have not
exceeded their quota limit can store data on the volume. The first time a user writes data to a
quota-enabled volume, default values for disk space limit and warning level are automatically assigned
by the quota system.
For more information about disk quotas, read the online help.
Adding storage
Expansion is the process of adding physical disks to an array that has already been configured.
Extension is the process of adding new storage space to an existing logical drive on the same array,
usually after the array has been expanded.
Storage growth may occur in three forms:
• Extend unallocated space from the original logical disks or LUNs.
• Alter LUNs to contain additional storage.
42 File server management