HP XP Racks - Manual (Page 42)

5 Monitoring and maintenance
This topic provides monitoring, editing, and maintenance instructions for external volumes, paths,
and systems.
Monitoring external volumes and paths
You can view system details about mapped external volumes, the ports used, and the external
paths.
Required Role
•
Storage Administrator (Provisioning)
1. In Remote Web Console, click External Storages in the Storage Systems tree.
2. Select the external storage system.
3. Select the path group.
4. Select the Mapped Volumes tab.
5. Select the external volume row. Click View External LUN Properties at the bottom of the window.
Related Topics
•
“View External LUN Properties window” (page 139)
Editing external volume policies (settings)
When you map new external volumes, preset mapping policies are used. You can change default
mapping values without affecting settings in previously mapped volumes.
To reset the values for previously mapped volumes, go to the Edit External Volumes window and
change settings volume by volume.
The settings and their functions are described in the following bullets. To skip to the procedure,
see
“Editing mapping policies ” (page 43) .
•
Base Emulation Type
Specify OPEN-V to use existing data in the external volume from HP XP7 Storage.
◦
◦ If you use an emulation type other than OPEN-V, the volume requires a specific area for
management data. This results in a volume capacity after mapping that is less than the
actual external volume capacity.
See “Capacity requirements for volumes ” (page 16) for more information about capacity
and calculating the capacity of your external volume.
•
Cache Mode. I/O to and from the local storage system always uses cache. Write operations
are always backed up in duplex cache. The Cache Mode setting specifies whether write data
from the host is written to the external volume asynchronously (Enable) or synchronously
(Disable).
◦ If Enable is specified: After receiving the data into the local system’s cache memory, the
system signals the host that the I/O operation has completed and then asynchronously
destages the data to the external volume.
◦ When Disable is specified (the default): After synchronously writing the data to the external
volume, the local system signals the host that an I/O operation has completed.
For further discussion, see “Cache use and external storage performance” (page 14) .
42 Monitoring and maintenance