System information
Using the RAID GUI
2-23
• Modify volumes
To modify a setting, select a volume and click Modify. Specify the following options for configuration.
To clear write buffers in the write cache of a volume, select a volume and click the Flush button.
• Create volume (VOL) snapshot volume pair
Instead of creating volume pairs in the Snapshot Volumes page, you can directly create volume pair to a specified
volume by clicking the S.VOL button. Specify a virtual disk as the secondary volume from the SV ID drop-down menu,
then click the Apply button to confirm.
• Detailed volume information
Click to display a complete list of volume information. You will see the following details.
2.6.6 Snapshot Volumes
This feature allows you to create, delete, and modify your snapshot volume settings. This is referred as the snapshot
technology. See 5.4 Snapshot on page 5-22 for more information.
• Create snapshot volume pairs (S.VOL.Pair)
Click Add to add a new snapshot volume pair before adding new snapshot volumes, where up to a maximum of 64
volume pairs can be created. Specify the following options for the configuration.
Name Type a name for the volume ID.
Preferred Controller This option is only available when the redundant-controller system is in use. Select
the preferred controller to be in charge of managing and accessing the volume.
However, the controller ownership will not change unless you check the ‘Change
owner controller immediately’ box.
Write Cache This option enables or disables the write cache of a volume.
Write Sorting This option enables or disables the sorting in the write cache. To improve writing
performance, it is recommended to turn this option on for random access. This
option is available only if the write cache is on.
Read Ahead Policy Always: The controller performs pre-fetching data for every read command from
hosts.
Adaptive: The controller performs pre-fetching only for host read commands that
are detected as sequential reads. The detection is done by read logs.
Off: If there is no sequential read command, read-ahead will result in overhead,
and you can disable the read-ahead.
Read Ahead Multiplier This option specifies the read ahead multiplier for the Always and Adaptive read
ahead policies. Select how much additional sequential data will be pre-fetched. The
default value is 8.
Read Logs This option specifies the number of concurrent sequential-read streams for the
Adaptive read ahead policy, and the range is between 1 and 128. The default
value is 32.
• VOL ID
• UUID
• Created Time and Date
• Alignment Offset (sector)
• Write Cache Status
• Write Cache Setting
• Write Sorting
• Read Ahead Policy
• Read Ahead Multiplier
• Read Logs
PVID From the drop-down menu, specify an LD as the primary volume of the volume
pair.
SVID From the drop-down menu, specify an LD as the secondary volume of the volume
pair.