User`s guide

Document Number: MAN-0057XX-000 Version 1.0
SteelVine
2 drives
SteelVine
SteelVine
3 drives
Drive A
Drive B
Drive A
Drive B
Drive C
SteelVine
SteelVine
SteelVine
4 drives
Drive A Drive B
Drive C
Drive D
8 drives
SteelVine
SteelVine
SteelVine
Drv A
Drv B
Drv C
Drv D
Drv E
Drv F
Drv G
Drv H
SteelVine
SteelVine
SteelVine
SteelVine
Level-1
Level-2
Level-3
SteelVine
Figure 9 - Cascading drive configuration options
Note: The SATA link between cascaded nodes in a cascaded configuration is not Port Multiplier aware.
Therefore, although it is possible to configure lower-level nodes (subordinate to the top-level mode) to
use JBOD, SAFE33 or SAFE50 Storage Policies, only the first volume for that node will be visible to any
upper-level node.
When creating virtual volumes with a cascaded configuration, ensure that all hard disk drives are
properly installed and that all SATA connections between the cascaded nodes are secure. You
must then configure the desired storage policy by setting the rotary switch and pressing the mode
change push-button on the
bottom-most nodes in the cascaded configuration, before configuring
any of the upper-level nodes. After the bottom-most nodes have been configured and become
ready, you can configure the middle nodes. Finally, the top-level node must be configured after
all subordinate nodes are ready.
If you wish to change the storage policy for any node or expand the storage capacity of any node
by adding more hard disks or SteelVine Storage Reference Design platforms, you must
reconfigure each node that has changed in the same bottom-up manner, and you must press the
mode change push-button to place the new storage policy into effect. The top-level node must
be the last item that is changed on the SteelVine Storage Reference Design platforms. In
addition, you must perform some supplemental steps on your host system so the expanded
volumes can be recognized at the file system and OS level. Refer to Appendix A, B or C for
information about to perform those steps on Windows, Macintosh and Linux systems.
Cascading also allows you to combine multiple SteelVine Storage Processors to create more
advanced RAID configurations for high-availability, such as RAID 10 (striping and mirroring),
as shown in Figure 10. The top-level node should be set to FAST (RAID 0) mode for striping,
and the subordinate nodes should be set to SAFE (RAID 1). In this configuration, the
subordinate nodes provide the protection of mirroring, and the top-level node provides the
performance benefits of striping. If one of the hard disk drives ever fails, the SAFE volumes
from the subordinate nodes will still be valid, and the RAID 10 set will still be available. When
the failed hard disk drive is replaced, the subordinate node will automatically rebuild the
mirrored volume.
57XX-Series SteelVine Manager User's Guide
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