HP NetServer AA 4000 Manual page 4

The following table lists the factors of tradeoff among the three configurations:
Local Backup
Backup Gives best backup
Performance performance.
Centralization of No centralization.
Backup Requires separate
management of
multiple tape drives
and multiple tape
cartridges. If data set
backed up is large,
this can require
significant IT
operator time.
Installation / Local backup
Configuration requires a separate
SCSI channel that is
not shared with hard
disks. A dedicated
Tape SCSI HBA
must be installed on
12/08/99
Semi-Local Backup
Backup performance is
good. But the virtual
network (or an extra
dedicated IOP network
card) is relatively slow,
the backup
performance for the
IOP disks is much less
than the rated tape
drive performance.
This may be acceptable
since the IOP, in
general, has very little
storage requirement.
Also, IOPs are static in
nature and they do not
need to be backed up
frequently. Overall, the
impact is moderate. (A
500MB IOP can be
backed up in as little as
20 minutes.)
No centralization.
Requires separate
management of
multiple tape drives
and multiple tape
cartridges. If data set
backed up is large, this
can require significant
IT operator time.
Semi-local backup on
the internal SCSI
channels is not
recommended because
normally both hot swap
cages (for LH series)
will be used and tape
Hewlett-Packard Co.
Network Backup
Slowest for backup
performance. Backup
network becomes a
major additional factor
that limits the
throughput of backup.
One should take into
consideration the
network bandwidth
that is shared among
many systems.
Network backup allow
a single backup server
to backup all the
systems from central a
data center. Tape
media management
should be less and IT
operator time is less,
since autochangers
hold more tape
cartridges. Backup
software aids in media
management.
Network backups
requires two additional
NICs in each IOP with
two additional IP
addresses to configure,
one on each IOP and
one on the CE.
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