Hewlett Packard Enterprise HPE XP7, User Manual, Page: 85 / 311

External Storage and external volumes used as pool-VOLs on page 71
Simultaneous processing of multiple Fast Snap pair tasks on page 71
Pair operations when pairs are cascaded on page 72
Pair operations when pairs are not cascaded on page 83
Data recovery and backup differences between Fast Snap and Business Copy on page 85
Fast Snap cache management device requirements on page 68
Data recovery and backup differences between Fast Snap and Business
Copy
Item Fast Snap (FS) Business Copy (BC)
P-VOL physical failures such as
hard disks. P-VOL data cannot be
guaranteed. P-VOL data can be recovered
using the S-VOL.
P-VOL logical failures such as
data update errors or viruses. P-VOL data can be recovered
using the S-VOL. P-VOL data can be recovered
using the S-VOL.
Capacity required for backup. Less capacity is required for
backups because only differential
data of the P-VOL is retained.
1
More capacity is required for
backup because all data in the P-
VOL is retained.
Impact on P-VOL performance
when accessing backed up data. P-VOL performance is affected
because data in the P-VOL is
shared.
2
P-VOL performance is not
affected because the P-VOL and
the S-VOL can be disconnected.
S-VOL or pool physical failures If a physical failure occurs in a
pool
3
, data in all S-VOLs that use
the pool cannot be guaranteed.
If a physical failure occurs in an
S-VOL, data in the S-VOL cannot
be guaranteed.
Notes:
1. For snapshot pairs. When a cloned pair is created, all data in the P-VOL is retained and more
capacity is required for backup.
2. For snapshot pairs. When a cloned pair is created, the P-VOL and the S-VOL can be separated and
the P-VOL performance is not affected.
3. When a pool is full (the depletion threshold is exceeded in a pool for which the capacity for FS pairs
is limited), data in all S-VOLs using the pool cannot be guaranteed.
Recommended usage
To maintain backed up data for long periods, save it on magnetic tapes or other media. For temporary
backups use FS or BC. When backing up data to magnetic tapes use BC. To reduce the capacity
necessary for backups use FS, but note that this affects P-VOL performance.
Use BC to minimize the impact from P-VOL physical failures. If you need four or more generations of
backups, use both BC and FS as shown in the following figure.
Data recovery and backup differences between Fast Snap and Business Copy 85