Dell PowerVault MD3800i - Manual (Page 8)

Introduction to Storage Arrays
A storage array includes various hardware components, such as physical disks, RAID controller modules,
fans, and power supplies, gathered into enclosures. The physical disks are accessed through the RAID
controller modules.
One or more host servers attached to the storage array can access the data on the storage array. You can
also establish multiple physical paths between the hosts and the storage array so that loss of any single
path (for example, through failure of a host server port) does not result in loss of access to data on the
storage array.
The storage array is managed by MDSM running on a:
• Host server — On a host server system, MDSM and the storage array communicate management
requests and event information using in-band or out-of band-connections.
• Management station — On a management station, MDSM communicates with the storage array either
through an Ethernet connection to the storage array management port or through an Ethernet
connection to a host server. The Ethernet connection passes management information between the
management station and the storage array connectivity.
Using MDSM, you can configure the physical disks in the storage array into logical components called
disk groups or dynamic disk group and then divide the disk groups into virtual disks. Disk groups are
created in the unconfigured capacity of a storage array. Virtual disks are created in the free capacity of a
disk group.
Unconfigured capacity comprises physical disks not already assigned to a disk group. When a virtual disk
is created using unconfigured capacity, a disk group or dynamic disk group is automatically created. If the
only virtual disk in a disk group is deleted, the disk group is also deleted. Free capacity is space in a disk
group that is not assigned to any virtual disk.
Data is written to the physical disks in the storage array using RAID technology. RAID levels define how
data is written to physical disks. Different RAID levels offer different levels of accessibility, redundancy,
and capacity. You can set a specified RAID level for each disk group and virtual disk on your storage array.
For more information about using RAID and managing data in your storage solution, see the Owner’s
Manual at dell.com/support/manuals.
Related Documentation
NOTE: For all PowerVault documentation, go to dell.com/support/manuals and enter the system
Service Tag to get your system documentation.
NOTE: For all Dell OpenManage documents, go to dell.com/openmanagemanuals.
NOTE: For all storage controller documents, go to dell.com/storagecontrollermanuals.
Your product documentation includes:
• Dell PowerVault MD3800i and MD3820i Storage Arrays Getting Started Guide — Provides an overview
of system features, setting up your system, and technical specifications. This document is also
shipped with your system.
• Dell PowerVault MD3800i and MD3820i Storage Arrays Owner’s Manual — Provides information
about system features and describes how to troubleshoot the system and install or replace system
components.
• Rack Installation Instructions — Describes how to install your system into a rack. This document is
also shipped with your rack solution.
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