IBM Storwize V7000, Introduction And Implementation Manual

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IBM Flex System V7000 Storage Node Introduction and Implementation Guide
4. On the Thin Provisioning tab (Figure 6-8), there are several advanced options available:
– Real: Specify the size of the real capacity space used during creation.
– Automatically Expand: This option enables the automatic expansion of real capacity, if
new capacity must be allocated.
– Warning Threshold: Enter a threshold for receiving capacity alerts.
– Thin Provisioned Grain Size: Indicates size of a single chunk of data on the volume.
The smaller grain sizes save space and larger grain sizes produce better performance.
– At any time if you are not sure what a specific option is and what it indicates, place your
cursor on the option the little “?” icon right next to the option and it will display the info.
Make your changes, if required, and click OK to return to Figure 6-7 on page 261.
5. In Figure 6-7 on page 261, click Create and the creation task completes as shown next in
Figure 6-9.
Figure 6-9 Create a thin-provisioned volume - CLI command displays
6. After the task is completed, click Close.
You can choose to map the new volumes immediately as part of the volume create wizard by
clicking Create and Map to Host. It will guide you through the Map to Host wizard described
in 6.3, “Mapping a volume to the host” on page 279.
6.1.3 Creating a mirrored volume
IBM Flex System V7000 Storage Node offers the capability to mirror volumes, which means
that a single volume is presented to the host, but two copies exist in the storage back-end,
usually in different storage pools (all reads are handled by the primary copy). This feature is
similar to host based software mirroring such as LVM, but it provides a single point of
management for all operating systems, and provides storage high availability to operating
systems that do not support software mirroring.