Feb 5, 2007 - Connectivity between host servers and the storage is pro- vided by two ... server using SAS and Modular Di
Storage
Exploring the Dell PowerVault MD3000 Storage System By Manjusha Gopakumar Vishal Kadam Paul Winston
T
The Dell™ PowerVault™ MD3000 external RAID enclosure allows multiple servers to access a shared pool of expandable storage, helping enterprises avoid the costs and complexities of internal storage. This article outlines the hardware, configuration, and management features of this storage system.
he Dell PowerVault MD3000 storage array is designed
checks, and Self-Monitoring, Analysis, and Reporting
to provide flexible, high-performance, highly scal-
Technology (SMART)
able RAID storage without compromising owner=0 segmentSize=16 capacity=2GB;
• Create a complete image of data on a virtual disk at a particular point in time
set virtualDisk["Test"] mediaScanEnabled=false; set virtualDisk["Test"] consistencyCheckEnabled=false; set virtualDisk["Test"] modificationPriority =high;
tasks:
• Provide quick, frequent, nondisruptive backups • Test new versions of a database system without affecting actual data • Enable snapshot virtual disks to be read,
Figure 5. Sample script for the Dell Modular Disk Storage Manager CLI 3
DELL POWER SOLUTIONS | May 2007
written, and copied Reprinted from Dell Power Solutions, May 2007. Copyright © 2007 Dell Inc. All rights reserved. Rev. 2.
www.dell.com/powersolutions
• Use virtual disk high-availability features,
can enable read/write access by changing
Deploying this storage system can allow enter-
such as RAID protection and redundant path
the target virtual disk permissions from
prises to implement highly available shared
failover
“Read-Only” to “Read/Write.”
storage and help them avoid the costs and
• Map snapshot virtual disks and make them
• Recover virtual disks: If a source virtual disk
accessible to any connected host, and make
fails, administrators can un-map this failed
snapshot data available to secondary hosts
virtual disk from its host and map its virtual
Manjusha Gopakumar is a senior engineer ana-
by mapping the snapshot to the hosts
disk copy to the same host.
lyst in the Test Case Design team at the Dell
• Create up to four snapshots per virtual disk • Increase the capacity of a snapshot virtual disk
complexities of internal storage.
Bangalore Development Center. She has a bach-
Storage partitions
elor’s degree in Computer Science from Rajiv
A storage partition is a logical entity consisting
Gandhi Technical University.
of one or more virtual disks that can be
Virtual disk copies
accessed by a single host or shared among
Vishal Kadam is a senior engineer analyst in
Administrators can use the PowerVault MD3000
hosts that are part of a host group. The first
the Test Case Design team at the Dell Bangalore
and Modular Disk Storage Manager to create
time administrators map a virtual disk to a
Development Center. He has a diploma in
exact copies of virtual disks. The target virtual
specific host or host group, a storage partition
Electronics and Communication and is currently
disk copy must be at least the same size as the
is created; subsequent virtual disk mappings
pursuing a degree in Information Technology
source virtual disk, and write access to the
to that host or host group do not create another
from the University of Mysore. He is a Microsoft
source virtual disk is blocked during the copy
storage partition. LUN masking is implemented
Certified Systems Engineer (MCSE), Sun Certified
operation. Administrators can specify some set-
using storage partitions.
System Administrator (SCSA), and Brocade Certified Fabric Professional (BCFP).
tings for the virtual disk copy, such as copy pri-
Administrators can use single storage parti-
ority and read/write permission, before or
tions or multiple storage partitions for different
during the copy operation.
purposes. Single storage partitions are useful
Paul Winston is a test engineer adviser in the
when only one attached host is accessing all of
Test Case Design team at the Dell Bangalore
the virtual disks in the storage array, or when
Development Center. He has a bachelor’s degree
all attached hosts share access to all virtual
in Commerce from Bharathiar University and an
• Copy data to larger disks: As storage require-
disks on the storage array; this type of configu-
advanced diploma in Software Engineering from
ments for a virtual disk change, administrators
ration requires that all hosts be running the
Aptech. His current interests include implement-
can copy virtual disks to a disk group within
same OS and special software (such as cluster-
ing storage area network, network attached stor-
the same storage array that uses drives with
ing applications) to manage virtual disk sharing
age, and cluster solutions.
larger capacity than the current drives.
and accessibility. Multiple storage partitions are
Administrators can use the virtual disk copy feature to perform the following tasks:
• Copy snapshot virtual disks: Administrators
useful when specific hosts are accessing spe-
can select snapshot virtual disks as source
cific virtual disks in the storage array, or when
virtual disks for virtual disk copies, which
hosts with different operating systems are
enables comprehensive backups while
attached to the same storage array; this type of
helping avoid significant impact on storage
configuration requires creating a storage parti-
array I/O.
tion for each type of host.
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• Assign virtual disk copies to hosts: Administrators can directly assign hosts to
Flexible, highly scalable storage
a target virtual disk, although by default the
The Dell PowerVault MD3000 is designed to
hosts do not have write access to the virtual
provide a flexible, highly scalable storage
disks, and an attempt to write to them
system with advanced features such as virtual
results in a host I/O error. Administrators
disk snapshot and virtual disk copy creation.
Reprinted from Dell Power Solutions, May 2007. Copyright © 2007 Dell Inc. All rights reserved. Rev. 2.
Dell PowerVault MD3000 User’s Guide: support.dell.com/support/edocs/ systems/md3000
www.dell.com/powersolutions
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