Simple, Reliable Performance for iSCSI Connectivity

The majority of server iSCSI connections
today use the integrated native OS
initiators, and the integration of the
initiator with the OS greatly simplies
the establishment of an iSCSI connection.
For example, these are the simple setup
steps required to use iSCSI connections in
Microsoft Windows Server* 2008:
1. Install Windows Server 2008.
2. Set up your target(s).
3. From Control Panel, launch the iSCSI
Initiator utility.
4. From the Discovery tab, add your target.
5. From the Targets tab, select the target,
and then click Log On.
6. After logging on, from the Bound
Volumes/Devices tab, bind all volumes.
7. Partition or format the disk as needed.
8. Start using your new network-
connected iSCSI volume.
In contrast to that simplicity, ofoad
engines and other proprietary solutions
force SAN administrators to rely on
hardware vendors to provide special-
purpose iSCSI initiators. Many of these
unproven initiators require frequent
rmware updates and reboots, have
unpredictable compatibility across
different applications, and are supported
on only a limited number of adapter types.
Moreover, most HBAs force the SAN
administrator to rely on a proprietary
TCP/IP stack, the critical link between the
host server and the network. OS vendors
have hardened and ensured the standards
compliance of their native TCP/IP stacks
over many years, making them robust
and dependable. As a result, most SAN
administrators are rightly reluctant to
take the unnecessary risk of moving from
trusted, OS-provided TCP/IP stacks to
unfamiliar, proprietary ones.
Many management applications are also
designed to use the native TCP/IP stack in
Windows or Linux. Therefore, ofoading
to a proprietary stack can defeat certain
optimizations that have been made to
those management applications or even
limit their reach in terms of their ability
to manage particular systems. More
specically, issues may arise with adapter
teaming, as well as security or monitoring
applications. Not surprisingly, support
for proprietary software stacks by open
source OSs and hypervisors can be
particularly limited.
A later section shows how Intel Ethernet
Server Adapters use this native OS
support and intelligent hardware ofoads
to deliver outstanding iSCSI performance.
Extending the Value of Centralized
Data Storage with Remote Boot
Using Intel® iSCSI Remote Boot, an IT
administrator can build an OS image and
start the server from a disk maintained on
the remote storage array instead of from
a locally attached hard disk. Maintaining
OS images on the SAN with Intel iSCSI
Remote Boot enhances many of the
benets of the SAN, including greater
centralized data storage and efciency,
as well as improved backup and disk
utilization.
In the past, a network boot or pre-boot
execution environment (PXE) server was
required to manage the remote boot
process. Intel Ethernet Server Adapters
store boot code in their local memory
and work with native boot support in the
OS to attach directly to the target SAN
storage unit during the power on and
boot stage. After boot, the adapter passes
control, authentication, and security
credentials to the native OS iSCSI initiator.
This process can be accomplished without
requiring additional management servers,
further simplifying the topology. This
approach is in contrast to that of some
iSCSI ofoad vendors that provide a
proprietary boot feature, which requires
administrators to accommodate a
specialized, proprietary process that is
likely not as mature as the native iSCSI
boot provided by most OSs.
Decoupling the OS image from the
physical server with Intel iSCSI Remote
Boot enables a consolidated virtualized
environment that can be centrally
managed with the following benefits:
• More efficient provisioning and
maintenance. Managing OS images from
a centralized console is more efficient
than doing so on distributed servers.
• Reduced hardware and associated
power requirements. Decoupling
storage from the physical server
eliminates the need for RAID cards and
local storage.
• Improved disaster recovery.
Virtual disks can be replicated to
another physical location, removing
the dependence on systems at the
primary site.
Intel has worked with major OS vendors
to provide remote boot capabilities with
native OS iSCSI initiators. Intel iSCSI
Remote Boot is designed to work with
most major OSs, including Microsoft
Windows Server and most Linux
distributions.
Consistent, Reliable Performance
across the Product Family
Intel Ethernet Server Adapters provide
enterprise-class drivers that work
together with the native iSCSI initiators
to deliver consistent, outstanding iSCSI
performance while reducing processor
utilization across GbE and 10GbE products.
The breadth of Intel’s offerings enables
IT organizations to increase performance
and lower costs by tailoring the network
connectivity solution to their specic
needs, assisted by advanced technologies.
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Simple, Reliable Performance for iSCSI Connectivity
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