APC SCSI-SATA II manual Snapshot /Rollback, Tips

Figure 4.3.1

Figure 4.3.2

(Figure 4.3.2: Extend UDV-R0 from 5GB to 10GB.)

Tips

The size of UDV extension must be larger than original.

Caution

UDV Extension cannot be executed during rebuild or migration.

4.4 Snapshot /Rollback

IS16GL Snapshot-on-the-box captures the instant state of data in the target volume in a logical sense. The underlying logic is Copy-on-Write -- moving out the to-be-written data to certain location whenever a write action occurs since the time of data capture. The certain location, named as snap UDV, is essentially a new UDV,.which can be attached to a LUN thus provisioned to a host as a disk just like other ordinary UDVs in the system. Rollback function restores the data back to the state of any point in time previously captured for whatever

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