HP StorageWorks All-in-One Storage Manager user guide (452695-004, November 2008)

Physical storage
NotesDescriptionItem
This value may be modified in order
to match the change rate of the
data in the storage area.
Amount of storage space (as a percentage of
the volume) that is reserved for storing snapshots
of the storage area.
Snapshot storage
space (percentage of
size)
Other storage settings
The percent full warning threshold
is set by default to 80%. Percent full
warning threshold values are
ASM-specific; percent full warning
threshold values selected in the
Quota Management MMC snap-in
are not adopted by ASM. All other
Quota Management MMC snap-in
settings are adopted by ASM. See
Setting a percent full warning
threshold on page 26.
The percent full value that when reached
changes the storage status to Warning and
issues a warning alert. The warning indicates
that storage use has surpassed the percentage
full value. For example, if you enter 75%, you
see a warning (yellow asterisk) in the content
pane when storage is at 75 percent full.
Percent full warning
threshold
This item is available for shared
folders and local storage
component. See Enforcing an
allocated storage limit for shared
folders and local storage
applications on page 26.
Sets an enforced quota for the amount of storage
available to a shared folder or local storage
application. When the storage space allocated
to a component is full, no further data can be
saved to this component.
Enforce allocated limit
(quota)
This setting does not apply to
shared folders.
Indicates whether the storage area is hosted on
a mount point or drive letter.
Application server
volume mount type
*After you have allocated and configured storage for an application component, user-defined application,
or shared folder using a wizard, you can change the allocated space size, change the percent full warning
threshold, and change the enforced allocated limit (shared folders and local storage applications). However,
you cannot change the RAID level, RAID stripe size, Hot Spares, or Physical Disk Type.
Customizing RAID levels
Before you customize the default RAID level setting, review Table 6 to see how the different RAID
levels affect performance, capacity, and data protection level.
Unless you customize the advanced configuration settings, the wizard configures the storage space
with the default values shown on the Advanced window:
• For Exchange and SQL Server, the wizard suggests default settings based on HP storage best
practices and specific recommendations for Exchange storage group and SQL Server database
components. You should generally accept these defaults.
• For user-defined applications and shared folders (where industry-standard recommendations cannot
be determined), the wizard provides default settings you can customize.
Table 6 shows how the different RAID levels affect:
• Performance–The speed at which data is read from and written to the hard drives. The RAID level
with the best performance rating provides the fastest reads and writes.
• Capacity–The available storage space on the hard drives. The RAID levels with the best capacity
rating require the least amount of storage space to store data.
• Data protection–The number of hard drives that can fail without data being lost. The RAID level
with the best data protection rating allows more hard drives to fail before data is lost.
Hosting storage for applications and shared folders24