If you receive errors when attempting to view this white paper, please install the latest version of
Adobe Reader.
“EqualLogic®, a leading provider of enterprise-class
iSCSI storage area network (SAN) solutions, has been awarded
SAN Product of the Year at the Techworld Awards 2007 for the PS3800XV storage array"
Source : Equallogic
How to Make Virtualized iSCSI SANs Work for You
ISCSI is also known as :
Internet Small Computer Systems Interface,
ISCSI SAN Solutions,
End to End Protocol,
ISCSI IP SAN Storage,
Virtual Infrastructure,
ISCSI Storage Arrays,
ISCSI Driver Acts,
ISCSI Target,
ISCSI Internet Scsi,
ISCSI Internet Small Computer System Interface,
ISCSI Protocol,
ISCSI PDF,
ISCSI Software,
Word ISCSI,
System And Storage Engineers,
ISCSI Target Server Software,
Use ISCSI ,
How To Create An ISCSI Target,
Functional ISCSI SAN,
ISCSI Consortium,
Network Protocol Standard,
Studio Network Solutions,
Download ISCSI Initiator,
ISCSI Allows Storage,
ISCSI Adapters Extend.
iSCSI is a flexible and powerful storage area networking (SAN) protocol that delivers superior capabilities and benefits
across all market segments. In addition to providing enterprise-class data availability and performance, the iSCSI protocol
enables breakthrough virtual storage designs that parallel the advanced designs of server virtualization technologies such
as VMware® Infrastructure 3.
Enterprises of all sizes are building flexible storage infrastructures using iSCSI and advanced virtualization technologies that
let them allocate and shift SAN resources dynamically in response to the demands of their virtualized server environments.
This white paper describes a virtualized infrastructure that applies storage and server virtualization technologies to cost-
effectively achieve a flexible, high performance, dynamic IT infrastructure that is simple to manage and scale.
WHAT IS iSCSI?
Developed by the Internet Engineering Task Force (IETF), iSCSI is a standard storage access protocol for interconnect-
ing servers and storage using an IP-based network interconnect. iSCSI is built upon the SCSI and TCP/IP protocols,
the dominant standards for storage and networking in use today. iSCSI is recognized for its simple integration,
interoperability, fundamentally lower costs, and its ability to leverage an organizations' inherent networking skills for
quick and broad adoption.
Software-based initiators, generally available for all major operating systems at minimal or no cost, take advantage of
standard Ethernet interfaces included as basic features of servers and desktops, enabling widespread deployment.
Easy access to this technology at little to no cost, coupled with the application of pre-existing IP networking skills
fundamental to today's IT organizations, provides for easy, affordable, and rapid adoption of iSCSI technology.
Using an ordinary IP network, iSCSI transports block-level data between an iSCSI initiator on a server and an iSCSI
target on a storage device. The iSCSI protocol encapsulates SCSI commands and assembles the data into TCP/IP
packets sent over the network using a point-to-point connection. Upon arrival at the storage device, the encapsulated
SCSI commands are unpacked from the TCP/IP packet for processing.
When an iSCSI initiator connects to an iSCSI target, the storage is seen by the operating system as a local SCSI device
that can be formatted as usual. The process is transparent to applications, file systems, and operating systems. By
consolidating storage with an iSCSI Storage Area Network (SAN), multiple platforms can share the same storage,
greatly improving utilization and efficiency.
The opportunity to use a standard Gigabit Ethernet NIC to connect servers to storage makes iSCSI both simple and
affordable. Today's high speed CPUs can run iSCSI at line speed over standard NICs using only a marginal amount of
CPU. Onboard Gigabit Ethernet NICs ship standard with servers, so no additional cost is incurred and the adminis-
trator need not bother with installing adaptor cards.
Together, standard NICs and the lower cost of Ethernet switches offer a compelling cost savings over Fibre Channel,
while maintaining the performance advantages of a SAN. However, the savings are not limited to the hardware costs
alone. With iSCSI, IT departments leverage their existing IP networking expertise, without needing specially trained
staff. This familiarity with the network infrastructure eliminates a key problem of complexity associated with Fibre
Channel SANs.
SERVER VIRTUALIZATION
Server virtualization is one of the most significant technology trends in IT today. Managing server hardware and
software as separate infrastructure components makes it
possible to significantly improve data center operating
efficiencies. At a high level, server virtualization works by
encapsulating ‘guest' operating systems into a set of
‘virtual machine' files. The operating system and its unique
execution variables and associated data sets are maintained in these files.
Given sufficient memory and disk storage, a single hardware system running server virtualization software can
support many guest virtual machines. Applications and
data are processed in exactly the same way as in the
physical environment, using the same operating system
facilities for making system requests. The only difference
is that the operating system is now a virtualized guest running in a virtual system environment.
Virtual machine files can be transparently migrated from one
server hardware platform to another, giving administrators
the ability to allocate and shift physical server resources in
response to changes in application workloads. A scalable,
highly resilient, flexible server environment is created, resulting in greater resource utilization, greater IT flexibility, and
lower operating costs.
STORAGE VIRTUALIZATION
Today, most IT professionals define storage virtualization as
a technology that allows discrete storage systems to operate as a single resource. In light of recent advancements in
server virtualization, the concept of storage virtualization is
being further refined as a way to create an abstraction layer
between the storage hardware and logical data volumes.
Given sufficient protocol support (as with iSCSI), virtual
storage products are now being designed that allow data
volumes to be located and striped across multiple (and
diverse) physical storage resources, including storage
systems, RAID groups, disk types, and controllers. Not
only does this provide higher performance and scalability,
it also allows data volumes to be transparently moved from
one set of resources to another without disruption to the
operating systems and applications that are utilizing data.
A scalable, highly resilient, flexible storage environment is
formed, resulting in better storage utilization rates and far
lower operating costs.
REQUIREMENT FOR NETWORKED ENTERPRISE
STORAGE IN A VMWARE INFRASTRUCTURE
In a VMware Infrastructure 3 environment, multiple
physical servers are networked into a cooperating set of
computing resources (see Figure 1). In lieu of a standard
Linux or Windows® operating system, each of the x86
standard servers run a copy of VMware ESX Server,
which provides the abstraction layer between the physical
servers and guest operating systems. Multiple ESX
servers are organized into an ESX cluster that are
controlled and coordinated by VMware's VirtualCenter, a
centralized management system.
Within the VMware environment, a virtual machine's configuration parameters, operating system, data sets, and
applications are encapsulated in a set of files managed by
the VMFS file system. VMFS is a clustered file system that
coordinates access across ESX servers, enabling the
ability to migrate live virtual machines across systems in
the ESX cluster.
The power of this architecture comes from the ability to
run any guest OS, its applications, and its data
without modifying any physical server in the cluster. As
the need arises, additional server resources can be
non-disruptively added to the ESX server cluster, and
current workloads are load balanced to take advantage of
the newly available resources.
Effective VMware deployments depend on shared access
to storage ' in other words, a SAN. SANs ensure that
each ESX server has immediate access to any virtual
machine's data sets, enabling immediate re-hosting of the
virtual machine. This eliminates the unacceptable and time
consuming necessity of copying virtual machine files,
applications, and data from one ESX server to another.
SANs support powerful features within VirtualCenter '
these include VMotion, the online migration of active
virtual machines without interruption, and Distributed
Resource Scheduling (DRS), which monitors and automatically migrates virtual machines to balance workloads
across all resources within the ESX cluster. VMware HA
monitors the proper functioning of ESX servers within the
cluster, and in case of an ESX server failure, re-hosts
and restarts virtual machines affected by the failure onto
another ESX server within the cluster.
In addition to the requirement for networked storage, a
virtualized environment heightens the need for high performance, highly available, resilient storage to meet the needs of
the aggregation of workloads. As more critical applications,
production workloads, and data assets are consolidated
into fewer resources, greater is the need for high performance, non-disruptive scalability, and continuous availability
of the storage assets. Enterprise-class storage, designed
for mission critical deployments is a basic requirement
when building a virtualized IT infrastructure.
In particular, purpose-built storage architectures should be
deployed that include mirrored memory write caches, fullyredundant hot-pluggable components, online hot spare
disks, environmental monitoring, and enterprise-class disk
drives with RAID protection. Furthermore, advanced availability features including storage controller and I/O path
failover are required to guarantee data access even in the
case of component failure.
Consideration should also be taken to evaluate the data
protection software features enabled within the storage
system. Storage consolidation within a SAN enables the
consistent application of data protection and disaster
recovery, assuming the basic SAN-based tools are
available and enabled. Space-efficient, non-intrusive
snapshot-based point-in-time copies as well as efficient
array-based replication tools should be considered as
basic requirements of the storage infrastructure for a
virtualized environment. Multiple use cases exist for the
application of these tools in virtualized environments
including disaster recovery, online backup and quick
recovery of virtual machines, simple extraction of lost or
corrupted data files, rapid virtual machine and data set
provisioning using snapshots and clones for production and
temporary use, as well as server-less tape- and disk-based
backup and recovery of the organization's data assets.
A thorough evaluation of the storage platform should be
considered prior to deployment, reflecting not only upon
the robustness and feature set, but also the total cost of
ownership over its useful life, with particular consideration
of the required system growth in terms of both performance and capacity.
ESX SERVER AND iSCSI
With the advent of VMware Infrastructure 3, iSCSI initiators are integrated into the ESX kernel, allowing native
access to iSCSI storage directly from ESX Servers. Both
hardware initiators (QLogicQLA4052C) and software
initiators are available. NIC teaming (multiplexing a single
logical connection across multiple interfaces) is supported
with the software initiator. The hardware initiator includes
support for multi-pathing as well as boot from SAN.
iSCSI support broadens the potential for full-fledged
VMware infrastructure deployments in the small and medium business market segment by obviating the need for a
costly and complex Fibre Channel SAN deployment. The
acquisition, implementation, and operational cost of an
iSCSI-based SAN are intrinsically lower, removing an
economic barrier to the adoption of server virtualization
technologies. In addition, but far less well recognized, is
the opportunity for advanced iSCSI-based system architectures to dramatically change customer expectations in
mid-market and enterprise deployments as well.
The addition of iSCSI protocol interfaces to classic
storage system designs do not fully exploit the potential of
the iSCSI protocol and, in turn, do not adequately solve
the storage management challenges faced today by
IT managers. Even with the introduction of iSCSI, the
storage administrators of classic storage system designs
require a rarified level of knowledge for configuring and
tuning storage arrays, RAID geometries and data layout
considerations, application workload analysis, forced data
migration and complex system upgrades.
HOW iSCSI ENABLES VIRTUALIZED SANS
Storage virtualization can simplify provisioning and ongoing management, increase storage utilization, provide
unlimited scalability in capacity and performance, and
enable online migration of data sets among controllers
and storage tiers. By consolidating network-based
storage into a simple, flexible, consolidated pool of storage that can arbitrarily grow in capacity and performance
(as in an EqualLogic environment), storage virtualization is
a key enabler for simplifying a virtualized IT infrastructure.
Historically, the adoption of storage virtualization technologies in SAN environments has been limited, primarily to
enterprise data centers needing a tool for online data
migration between heterogeneous storage environments.
This add-on design allows for heterogeneous storage and
data movement, but does not simplify management of
the configuration. Most of these designs have been
implemented as external appliances sitting within the
storage area network. These devices generally add more
complexity to an already complex environment ' introducing additional points of management within the SAN,
masking value-added features of the attached arrays, and
limiting performance and scalability of the consolidated
SAN storage pool to a single gateway hosting the
backend storage. In the iSCSI realm, simpler design alternatives make the promises of storage virtualization easier
to achieve.
The most advanced storage virtualization technologies
offer the ability to virtualize storage at the storage device
level. This approach achieves scalable performance and
capacity and reduces overall management by aggregating
multiple controllers into a cooperating set of resources,
i.e., virtualizing volumes not only across disks within a controller but also across storage systems in a SAN.
EqualLogic PS Series storage arrays are an excellent
example of such a "scale-out" architectural design.
Ironically, despite their elegant simplicity, such designs are
virtually non-existent in the Fibre Channel SAN world,
primarily due to architectural constraints inherent in Fibre
Channel network deployments.
Devices in a Fibre Channel SAN are attached to the
network via a World Wide Name (WWN), a physical port
address specifically assigned and encoded within the
device hardware/firmware. World Wide Names are
assigned for all devices within the SAN, including each
physical port within each host server and each physical
port within the storage controllers. Furthermore, data
paths between the hosts and the storage array are
statically set when the host is added to the SAN.
Herein lies the inflexibility of Fibre Channel SANs. The
topology of the SAN is intrinsically hard coded into the
environment, making changes within the infrastructure
burdensome, time consuming, and error-prone. Expansion
of resources in the host, fabric, or storage layer propagates changes throughout the infrastructure, causing
intrusive downtime to the applications and infrastructure.
In contrast, TCP/IP networks support virtual addressing
and dynamic routing, whereby paths through the network
are not statically defined. With DHCP, addresses can be
dynamically assigned, or through address proxying,
physical addresses can be virtualized, making it possible
for devices in the network to transparently act on the
behalf of other devices on the network. If the IP
address of the resource being accessed is known from
within the network, the entity (such as a SAN initiator)
requesting access can find the resource dynamically
without prior knowledge of the paths or the resource's
physical address.
IP address proxying makes storage access fully virtualized
across multiple EqualLogic storage controllers. In an
EqualLogic group, for example, each member array has 3
active physical gigabit Ethernet ports. A 4-member group
has a total of 12 active Ethernet ports, providing 12
Gb/second of peak bandwidth. Each of these Ethernet
ports is assigned an IP address. The members within the
group are aware of and coordinate use of these multiple
IP addresses and the underlying physical resources.
External access to the group by all hosts within the SAN
is exclusively addressed via the group IP address, a
unique IP address that transcends all the underlying member IP addresses. The only IP address known by the
attached hosts in the SAN infrastructure is the group IP
address. All I/O's may be serviced by any physical gigabit
Ethernet port.
Shielding host systems within the SAN from being aware
of the physical topology of the storage serving its data
is vitally important, particularly in a virtualized server
environment. By virtualizing all physical I/O ports, a flexible
storage utility is created. Pooling storage assets within the
SAN is now possible, enabling a rich set of features to
maximize storage utilization and effectiveness, extending
beyond the limitations of a single, physical end-to-end
connection to a single storage controller.
Data is accessed by the host without intimate knowledge of where in the storage utility the data is stored,
providing the opportunity for data volumes to span
controller boundaries and exploit the combined
resources of multiple controllers. Controllers coordinate
among themselves to balance workloads and optimize
storage resource utilization.
Changes in storage infrastructure can be achieved
seamlessly, without impacting host connectivity or data
access. The iSCSI-based infrastructure can be scaled
non-disruptively, automatically applying the resources of
the additional controllers and disks to extend performance and capacity. Multiple tiers of storage can be
seamlessly integrated in the utility, providing for automatic placement of data within a volume to the appropriate
tier based on the volume's access patterns.
A flexible storage architecture as described above is
particularly appealing in a virtualized server environment
as the "scale out" architectures of both server and
storage infrastructures uniquely complement each other,
providing an end-to-end virtualized infrastructure.
Deployed together, IT managers achieve an infrastructure that is particularly adaptable to changing business
requirements by providing non-disruptive workload
migration and balancing across all physical resources
(both storage and server resources) as well as online
resource expansion that immediately apply to pre-existing server and storage workloads without intervention
and tuning.
EQUALLOGIC VIRTUALIZED iSCSI SANS
A virtualized iSCSI SAN complements ' and is character-
istically equivalent to ' a VMware ESX server farm.
The foundation of an EqualLogic virtualized iSCSI SAN
(see figure 2) is the PS Series storage array. Each array is
fully-redundant, containing disks, multiple high-perform-
ance network interfaces, redundant controllers with
mirrored battery-backed caches, and other advanced
features. The disks are automatically protected with RAID
(RAID 10, RAID 50, or RAID 5) and hot spares. Multiple
models of arrays exist, leveraging high performance 10K
and 15K RPM SAS drives or more cost effective, higher
density SATA-II drives.
A PS Series storage group is comprised of a single
PS Series array or multiple arrays. A group is a virtualized
resource, appearing to ESX servers as a single entity that
offers network storage access to a single large pool of
storage ' a storage area network (SAN) composed of a
single, virtually scalable, high performance storage
system. Unlike a conventional SAN, in which multiple
controllers appear as independently managed islands of
storage, each group member in an EqualLogic SAN
"cooperates" with other members to automate resource
provisioning and performance optimization.
ESX administrators create data volumes from within the
EqualLogic group storage pool. The group exports its vol-
umes as iSCSI targets protected with security, including
authentication and authorization. Upon connection, ESX
servers work with EqualLogic's volumes as VMFS
DataStores, which contain multiple virtual machines and
virtual disks. A variation on this is a Raw Device Map in
which the SAN-resident volume is mapped directly to
correspond to a virtual disk within the ESX environment,
circumventing the VMFS DataStore. A third alternative is
to employ the native iSCSI software initiator of the individ-
ual guest operating system to connect directly to the
SAN-resident volume.
AUTOMATIC LOAD BALANCING
Volumes are distributed among the group's member
arrays, with data placement and access continually adjust-
ed for optimal performance as resources are added or
workloads change. When an array is added as a group
member, its disk space is added to the group's storage
pool. Volumes are automatically re-striped and distributed
across all the members of the storage pool. Controller
resources are also dynamically adjusted based on the
workloads being generated by the ESX server farm. Data
and network I/O to the group are automatically load
balanced across the group members' resources.
As capacity and performance requirements increase, a
group can be scaled linearly in both capacity and perform-
ance ' all while online. New members "learn" configura-
tion and performance information from the group ' with no
manual intervention. Data and client connection load
balancing occur automatically as the group scales. I/O
activity is monitored, and data and network connections
are adjusted as needed.
NON-DISRUPTIVE SCALABILITY
The scalability model allows for automated, online
expansion in all storage dimensions, and the PS Series
architecture nearly eliminates downtime caused by
expanding or managing a storage system. Because
capacity can be added so easily, IT managers need to buy
only the storage necessary for today's applications, easing
budget constraints caused by excessive purchases.
Additional benefits of the virtualized SAN environment
include the transparent application of storage tiers.
EqualLogic storage groups can use multiple storage tiers
contained within the storage pool and automatically
optimize data placement based on workload. Alternatively,
storage tiers may be segmented into independent
resource pools to guarantee specific resources to
specific workloads, concurrently maintaining the flexibility
to migrate volumes online from one tier to another, fully
transparent to the ESX host servers.
END USER CASE STUDY: COSTAR GROUP, INC.
CoStar Group, Inc., based in Bethesda, MD, is recognized as the number one provider of information services to
commercial real estate professionals throughout the United States as well as in the United Kingdom and France. Every
day industry professionals throughout the U.S., U.K. and France depend on Internet access to CoStar's services, tools
and analytics as their business information lifeline. Today, CoStar's database contains over 2.3 million verified and con-
tinuously updated commercial properties representing more than 40 billion square feet of inventory as well as over
800,000 properties actively being marketed for sale or for lease.
With more than 13,000 client sites and approximately 75,000 subscribers to CoStar's online database, a robust, scala-
ble IT infrastructure is vital to the company's success and future growth. Consequently, CoStar is always looking for
ways to enhance and simplify its technology infrastructure.
CoStar turned to virtualization to reign in an expanding IT footprint and reduce management costs. The company
built a virtualized IT environment based on VMware Infrastructure 3 and an EqualLogic PS Series virtualized iSCSI SAN
as a key element of their infrastructure.
By leveraging both server and storage virtualization, CoStar has architected a solution
to reduce its IT footprint, increase responsiveness for provisioning new IT assets,
simplify the ongoing management of both servers and storage, and seamlessly scale
their infrastructure over time.
VIRTUALIZED SERVERS
The production environment includes 8 ESX Servers based on
dual & quad-processor, dual-core Opteron-based servers
each with 24 to 32 GB's of RAM in support of a phased rollout
of more than 200 virtual machines. Three additional ESX
Servers are dedicated to test and development. Qlogic
QLA4052C iSCSI HBAs are configured in each of the ESX
Servers to enable SAN boot capability, Jumbo Frames
support, and reduced I/O processing overhead.
At present, 115 virtual machines are in production, hosting a
variety of Windows Server 2003R2-based applications including
SQL databases, time accounting, source control, helpdesk
applications, data creation and management tools, and internal
back office processing. VMware's VMotion and High Availability
(HA) features are actively used for workload balancing, proac-
tive maintenance, and increased application availability.
VIRTUALIZED STORAGE
The storage backbone of the VMware infrastructure is an
EqualLogic virtualized iSCSI SAN, connected with the ESX
Server environment over a fully redundant gigabit Ethernet
fabric. Comprised of 5 EqualLogic PS3600X arrays, the
EqualLogic group contains 80 high performance, 10K RPM
Serial-Attached SCSI (SAS) disks configured as RAID-50 with
hot spares, for a total usable capacity more than 15 terabytes.
Currently, the 11 ESX Servers access nearly 4 TB's of provi-
sioned storage, configured as 8 VMFS file systems and 11 ESX
boot volumes, all resident on the EqualLogic SAN. Each
VMFS file system's data volume is auto-load balanced across
the 5 member arrays and all the disk drives in the SAN. The
aggregation of workloads from across 100 virtual machines in
the 8-member ESX Server cluster produces a random work-
load profile that particularly benefits from the multi-controller
architecture and aggregate performance of the large number
of fast spinning drives.
FUTURE DIRECTIONS
Future expansion of CoStar's virtualized infrastructure will
include the rollout of an additional 100 virtual machines,
including their Exchange environment and additional SQL
Server databases. CoStar is also planning to add a second tier
of virtualized storage; the EqualLogic group will be expanded
online to include two additional SATA-II-based PS400E arrays
as a 20 terabyte secondary storage pool. The EqualLogic
instant cloning and online volume migration features will be
used to quickly generate test and development environments
from production data.
Additional focus will also be placed on disaster recovery
processes; a second EqualLogic group, comprised of 2
PS3600X arrays, is already in place as the disaster recovery
target for the VMFS file systems. Using EqualLogic's autorepli-
cation feature, the production VMFS volumes are being
replicated to the EqualLogic group at the corporate DR site.
QUICK, INTELLIGENT PROVISIONING
Within the EqualLogic environment, storage is quickly
provisioned simply and easily with the click of a button.
The key functions needed to configure, manage and scale
storage is automated, cutting administration tasks for
volume and capacity growth. Given the intelligence built
into the PS Series software, decisions with respect to
RAID type and data layout are made automatically at time
of provisioning, and optimized as workload patterns for the
newly provisioned storage evolve. As new resources
become available, the resources are automatically applied
where and when needed. By eliminating complex tasks
and enabling fast and flexible storage provisioning,
PS Series solutions dramatically reduce acquisition
and ongoing operational costs and make enterprise
class shared block storage practical for the mid-range
storage market.
Thin provisioning extends EqualLogic's existing provision-
ing features. This makes the buy-as-you-grow storage
model of the modular PS Series more seamless for
servers and applications. Thin provisioning is an important
advanced feature which enables the automatic addition of
physical capacity on demand up to preset limits. With
advanced thin provisioning, buy-as-you-grow storage
management and virtualization are made seamless for
servers and applications. When a volume is created, it
can be sized for the long term needs of the application
without initially allocating the full amount of physical
storage. Instead, as the application needs more storage,
capacity is allocated to the volume from a free pool.
EqualLogic's thin provisioning capability provides exten-
sive flexibility and user safety controls. These include the
ability to turn thin provisioning on and off as needed for
any volume. This allows users to affordably test the most
suitable applications and volumes for thin provisioning,
with the knowledge that they can return to "normal"
provisioning online. EqualLogic's implementation of thin
provisioning also provides enhanced alerts and controls '
with proactive, user-defined threshold alarms and controls,
administrators can depend on automatic space allocation
without worrying about reaching allocation limits or
unexpected depletion of physical storage.
AUTOMATED MANAGEMENT
The PS Series architecture is designed to simplify storage
management in several ways. RAID configuration and hot
sparing is automated, and dynamic storage and network
I/O load balancing occurs automatically as resources and
performance metrics change. No longer must administra-
tors manually map application data to specific physical
devices and controllers.
A primary benefit of this automated, virtual storage system
is that storage administration remains stable as the group
is expanded. All administration is performed at the group
level, through the EqualLogic Group Manager, an intuitive,
single-pane administrative console. Because the group is
managed as a single logical system, the ongoing opera-
tional costs of storage management remain fixed even as
storage grows.
A FLEXIBLE, SCALABLE, VIRTUALIZED
ENVIRONMENT FOR SERVERS AND STORAGE
iSCSI is a key technology enabling scalable, cost-effec-
tive, high performance virtualized SAN environments,
a perfect complement to a virtualized server environment.
The storage virtualization achieved in the advanced iSCSI-
based design of the EqualLogic PS Series enables
greater performance, scalability, ease of use, and flexibility
in contrast to classic storage array architectures. As a
result, both server and storage assets become fully
virtualized (see Figure 3), abstracted from the physical
hardware upon which they reside. Virtualized server assets
leverage a pooled set of physical server resources.
Similarly, virtualized storage volumes leverage a pooled
set of physical storage resources.
By combining virtualized server and virtualized storage
technology, a simple, flexible IT infrastructure is created,
resulting in a comprehensive solution with a common set
of benefits, resulting in increased IT flexibility, lower total
cost of ownership and reduced complexity. These benefits
include:
- Aggregation of Virtualized Assets on Consolidated
Hardware ' Operational procedures and best practices
can be standardized and consistently applied to both
storage and server assets (both physical and virtual)
resulting in a more resilient infrastructure with greater
resource utilization, higher levels of service, and
enhanced protection of information assets.
- Simple, Centralized Management ' Greater management
efficiencies are achieved by centralizing management
through intuitive, graphical management tools accessible
from anywhere on the network, providing a comprehensive
view to provision, monitor, and manage the entire virtual-
ized infrastructure.
- Flexible and Quick Deployment of Virtualized Resources '
Organizations can quickly adapt to changing and growing
business needs by reducing the time to provision and
deploy new applications via quick provisioning methods
available for both servers and storage.
- Online, Non-disruptive Resource Re-allocation and
Expansion ' As workflows and business priorities change,
both storage and server resources can be simply re-allo-
cated online, with no disruption to operations. In addition,
physical resources can be easily expanded online without
downtime. Workloads are automatically rebalanced
across these newly available resources without disruption
to applications.
- Common IP Network-based Infrastructure ' The IT
environment is simplified by basing all operations on IP
networking, including the interconnect for client access,
inter-server communication, storage access, and off-site
data replication. The organization's inherent IP networking
expertise is leveraged, resulting in lower training and
ongoing management costs.
- Enterprise-class Resiliency ' With redundancy built into
the physical server, network, and storage architecture, as
well as component failure detection and failover software
implemented within each layer of the infrastructure, overall
reliability, availability, and service levels are enhanced.
- Advanced Data Management and Disaster Recovery '
A rich set of server and SAN-based data protection tools
ensure the organization's critical assets are protected and
immediately recoverable at the local or a remote site.
SUMMARY
Virtualized iSCSI SANs are changing customer experi-
ences of how simple an enterprise storage infrastructure
can be to deploy, manage, and grow. They are uniquely
positioned to enable broad adoption of virtualized server
technologies by reducing technical complexity and cost
barriers imposed by classic storage area network architec-
tures, without compromising the performance, scalability,
and resiliency requirements of a virtualized IT infrastructure.
As a result, organizations of all sizes are now deploying
EqualLogic PS Series virtualized iSCSI SANs as the back-
bone of their virtualized infrastructure.
Characteristically, both server and storage virtualization pro-
vide key features for reducing complexity and increasing
flexibility, including virtualized asset management, incremen-
tal online growth, workload migration, and load balancing.
The complementary effects of EqualLogic virtualized iSCSI
SANs and virtualized server technologies enable a simple,
cost-effective, and dynamic enterprise-class IT environment.
For more information regarding EqualLogic solutions,
contact us at 888-579-9762 ext 7792 or visit
www.equallogic.com.
For more information on EqualLogic solutions in a
VMware environment, visit www.equallogic.com/vmware.
For a live, web-based product demonstration, visit
www.equallogic.com/demo.
110 Spit Brook Road,
Building ZKO2,
Nashua,
NH 03062
Tel 603.579.9762 / Fax 603.579.6910 / www.equallogic.com
Flexible, Scalable Enterprise Storage
for Virtual Infrastructures