Each PowerVault MD3460 storage array can be expanded to a maximum of 120 (or 180, if enabled using
Premium Feature activation) physical disks through a maximum of two MD3060e series expansion
enclosures.
Cabling The Storage Array
You can cable the storage array to host servers with:
• Single path data configuration — A single path configuration allows you to connect a maximum of
eight hosts. This is a non-redundant configuration.
• Dual path data configuration — A dual path configuration allows you to connect a maximum of four
hosts.
You choose the data configuration based on:
• Number of hosts required
• Level of data redundancy required
Redundant And Non-Redundant Configurations
Non-redundant configurations are configurations that provide only a single data path from a host to the
storage array. This type of configuration is only recommended for non-critical data storage. Path failure
from a failed or removed cable, a failed HBA, or a failed or removed RAID controller module results in loss
of host access to storage on the storage array.
Redundancy is established by installing separate data paths between the host and the storage array, each
path is to one of the two RAID controller modules installed in the storage array. Redundancy protects the
host from losing access to data in the event of path failure, because both RAID controller modules can
access all the disks in the storage array.
Dual Controller Configurations
The following figures show two and four hosts, each connected to two RAID controller modules. Since
each host has redundant paths, loss of a single path would still allow access to the storage array through
the alternate path.
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