User`s guide

Document Number: MAN-0057XX-000 Version 1.0
available storage capacity. If either hard drive fails the primary data stored on the SAFE volume
would still be available whereas the temporary data stored on the BIG volume would be lost.
The size of the SAFE volume of a SAFE50 policy will be one-half of the size of one hard drive
(if they are equal) or one-half of the size of the smaller (if they are not equal). The size of the
BIG volume will be the combination of all remaining capacities.
Example: In Figure 7 below, assume that Drives A and B are 300 GB each. When the SAFE50 Storage
Policy is selected, the resulting virtual volumes will include SAFE volume of 150 GB (1/2 of 300 GB) and
a BIG volume of 300 GB (the remaining capacity after allocating 150 GB from each of the hard drives).
SteelVine
Drive A Drive B
Port 0
Port 1
SAFE BIG
Figure 7 - SAFE50 storage policy sample configuration
When using a SATA host connection, you must have a PM (Port Multiplier) aware host adapter
when using SAFE50 on the top level node of a cascaded configuration so that ALL volumes can
be detected by the host. If your SATA host adaptor is not PM aware, then ONLY the SAFE
volume will be detected and the BIG volume will not be accessible. No such limitation exists
when using a USB host connection.
For subordinate nodes in a cascaded configuration, it is possible to configure the SAFE50
storage policy, although you will only see the SAFE volume from that node. Therefore, the
SAFE50 storage policy should only be used at the top-level node of a cascaded configuration.
In this mode, the
Schedule/Verify option is enabled.
Refer to the
Capacity Expansion for SAFE33 & SAFE50 section below for additional
information about expanding the storage capacity for the SAFE50 Storage Policy.
Capacity Expansion for SAFE33 & SAFE50
When using the SAFE33 and SAFE50 storage policies, it is possible to begin with a single hard
disk drive, and then add a second hard disk drive to increase the size of the BIG virtual volume
(and to provide the data protection of the SAFE volume using mirroring) when additional hard
disk storage capacity is added.
57XX-Series SteelVine Manager User's Guide
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