How storage fits into blade servers

NETWORK WORLD NEWSLETTER: MIKE KARP ON STORAGE IN THE ENTERPRISE
08/25/05
Today's focus: How storage fits into blade servers

Dear networking.world@gmail.com,

In this issue:

* Storage blades
* Links related to Storage in the Enterprise
* Featured reader resource
_______________________________________________________________
This newsletter is sponsored by Ciena
Protect your mission critical data. Achieve regulatory
compliance. Ensure high availability.

Download Ciena's solution brief that discusses MAN/WAN solutions
that are EMC qualified for distance replication to help you meet
your business continuance and disaster recovery goals. Learn how
to reduce networking costs and meet the strict performance
requirements of these time-sensitive applications.
http://www.fattail.com/redir/redirect.asp?CID=110906
_______________________________________________________________
THE ROI OF VOIP

When it comes to VoIP, most network managers are satisfied that
the technology works. But there are questions: What will the new
technology cost to roll out and support, and what benefits can
companies expect to reap? Check out NW's step-by-step guide on
how to determine the true cost and benefits of VoIP. Click here:
http://www.fattail.com/redir/redirect.asp?CID=110698
_______________________________________________________________

Today's focus: How storage fits into blade servers

By Mike Karp

Last time, we mentioned some of the values blade servers deliver
- limited impact on floor space, device consolidation and
centralized management. But the overwhelming majority of server
blades are processor blades. What about blades for storage?

Several companies are looking to build storage blades into their
blade server lines. Last March IBM committed to developing
storage blades for its eServer line, and has already come out
with an early version of a blade holding six 2.5-inch SCSI
drives. According to IBM this blade is aimed mostly at providing
boot-up services for the various blades within the chassis, and
is not intended to be a general-purpose storage blade. But six
devices could offer in excess of 600G bytes of storage; even
mirrored, this seems like quite a bit of capacity for booting
purposes.

HP is developing a Serial Attached SCSI (SAS) storage blade for
its BladeSystem servers as a way to offer customers a scalable
system for computing, networking and storage. Right now it looks
as if the system will be ready for launch by year-end.

The choice of SAS for blade storage is an interesting one. SAS
devices will be relatively cheap compared to Fibre Channel
because they are well along in the process of becoming the first
choice for direct-attached storage, and thus the per-unit costs
should be starting to drop in the not-too-distant future.
Additionally, SAS connectivity can help address some of the
limitations that are sure to appear in a server chassis.

What? Limitations in a blade server? You bet.

For one thing, it is not at all clear how scalable the present
generation of blade servers is going to be. Scalability will
mean much more than finding room in the server frame for another
blade; it will also require adequate amounts of power, cooling
and networking capability.

SAS drives will help with the cooling issue in two ways. First,
the smaller connectors needed for the serial link to the
backplane will make some contribution to improving air flow
(although the smaller form factor drives will make a much
greater contribution). More importantly, the new generation of
drives draw less power than the previous generation - a feature
of the drive electronics and not a SAS feature, but nonetheless
a feature that SAS takes advantage of. Scaling will thus be less
stressful on power requirements and will run cooler as well.

The networking challenge will be no different than the
networking challenge that comes with any large mass of storage -
if the connectivity does not scale in proportion to the data
that needs to be moved, throughput will be throttled and will
never scale. The maximum amount of storage will thus be
effectively capped by the total amount of data than can be moved
on and off the server. SAS won't help that, but there may be
other solutions in the works.

Still, SAS devices would seem to fit pretty well with the needs
of a storage blade. Chip builder PMC-Sierra thinks so, at any
rate. The company has announced a full family of SAS "zoning
switch" silicon, which will enable segregation between broadcast
and SAS traffic, and which can ensure access control from any
device group to any other device group - and that will lead to
more easily managed resource sharing. Most readers won't care
about this. Most system builders will.

As things stand right now server blades are often more
cost-efficient, smaller and consume less power than traditional
servers. But it is likely there is a limit to their scalability.
The guidance when looking at blade servers for storage would
then seem to be that, at least as the technology stands right
now, they are likely a cost-effective alternative for the
midrange, but have no way of scaling to the point where they can
be expected to challenge high-end arrays.

The top 5: Today's most-read stories

1. Zotob worm also targets Windows XP
<http://www.networkworld.com/nlstorage5852>

2. Dr. Internet: Installing DHCP on Linux
<http://www.networkworld.com/nlstorage5853>

3. Cisco preparing management play
<http://www.networkworld.com/nlstorage5632>

4. IP PBXs outsell traditional PBXs, study says
<http://www.networkworld.com/nlstorage5854>

5. Test: Xirrus XS-3900 offers out-of-this-world Wi-Fi capacity
<http://www.networkworld.com/nlstorage5855>

Today's most-forwarded story:

IP PBXs outsell traditional PBXs, study says
<http://www.networkworld.com/nlstorage5856>

_______________________________________________________________
To contact: Mike Karp

Mike Karp is senior analyst with Enterprise Management
Associates, focusing on storage, storage management and the
methodology that brings these issues into the marketplace. He
has spent more than 20 years in storage, systems management and
telecommunications. Mike can be reached via e-mail
<mailto:mkarp@enterprisemanagement.com>.
_______________________________________________________________
This newsletter is sponsored by Ciena
Protect your mission critical data. Achieve regulatory
compliance. Ensure high availability.

Download Ciena's solution brief that discusses MAN/WAN solutions
that are EMC qualified for distance replication to help you meet
your business continuance and disaster recovery goals. Learn how
to reduce networking costs and meet the strict performance
requirements of these time-sensitive applications.
http://www.fattail.com/redir/redirect.asp?CID=110905
_______________________________________________________________
ARCHIVE LINKS

Archive of the Storage newsletter:
http://www.networkworld.com/newsletters/stor/index.html

Breaking storage news and analysis:
http://www.networkworld.com/topics/storage.html
_______________________________________________________________
EXCLUSIVE HOW-TO WEBCAST - Proactive Endpoint Security.

You can't have a winning endpoint security solution until you
can define it: Easy to deploy and manage, simple to use, minimal
user impact, real-time monitoring and notification, flexible
reporting and low total cost of ownership.
http://www.fattail.com/redir/redirect.asp?CID=110751
_______________________________________________________________
FEATURED READER RESOURCE
IT STAFF SHORTAGE LOOMING

Outsourcing. Automation. Downsizing. The industry has been awash
in unemployed IT pros. But experts are now predicting an IT
staffing crunch is just around the corner, and the implications
for U.S. technology innovation are sobering. What might be
causing the shortage and what might need to be done to prevent
it? Click here:
<http://www.networkworld.com/nlstorage5857>
_______________________________________________________________
May We Send You a Free Print Subscription?
You've got the technology snapshot of your choice delivered
at your fingertips each day. Now, extend your knowledge by
receiving 51 FREE issues to our print publication. Apply
today at http://www.subscribenw.com/nl2

International subscribers click here :
http://nww1.com/go/circ_promo.html
_______________________________________________________________
SUBSCRIPTION SERVICES

To subscribe or unsubscribe to any Network World e-mail
newsletters, go to:
<http://www.nwwsubscribe.com/Changes.aspx>

To change your e-mail address, go to:
<http://www.nwwsubscribe.com/ChangeMail.aspx>

Subscription questions? Contact Customer Service by replying to
this message.

This message was sent to: networking.world@gmail.com
Please use this address when modifying your subscription.
_______________________________________________________________

Have editorial comments? Write Jeff Caruso, Newsletter Editor,
at: <mailto:jcaruso@nww.com>

Inquiries to: NL Customer Service, Network World, Inc., 118
Turnpike Road, Southborough, MA 01772

For advertising information, write Kevin Normandeau, V.P. of
Online Development, at: <mailto:sponsorships@nwfusion.com>

Copyright Network World, Inc., 2005