> Cover Story
shape up for scalability, availability
mainframe computers continue to exist, servers rule the
roost in today's businesses, and borrow from mainframe designs
threat to Unix servers has increased now that Intel has
launched its 64-bit processor. Itanium's new architecture
has attracted manufacturers of RISC-based servers
IT managers look for multi-processor servers, starting with
a single or dual-processor system, and scaling up to several
ago, the mainframe
hogged floor space in a computer room, and was the heart
of a corporation's IT infrastructure. Mainframes (now much
smaller in size) continue to chug along in large corporations,
but smaller and more powerful servers are more widespread.
The computing environment in enterprises has evolved from
central processing unit to distributed
computing units (servers) spread out over a network. Today
there are servers dedicated to specialized tasks like primary
storage, Web hosting, telecommunications, file & print
services, application and database hosting etc. The demand
for servers has risen in the past year as more businesses
got e-enabled and began transacting over the Internet. This
resulted in the formation of Internet Data Centres (or server
farms) and the expansion of enterprise networks. Anyone
shopping for a server today has to make important decisions
about processors, brands and other technical specifications.
But the key requirements for today's fast expanding businesses
are scalability, availability, capacity, processing power,
uptime, and ease of management.
Mainframes or servers?
Not long ago, IT managers thought that RISC-based (Unix)
servers would replace ageing mainframes. However mainframe
computers are still manufactured today, although they have
shrunk in size considerably. Some enterprises continue to
hang on to legacy systems and even use middleware to tie
these in with Web front-ends or new IT infrastructure. While
new mainframes are sold mainly to large public utility and
financial organizations, Internet driven businesses favor
Meanwhile server manufacturers are taking the best from
mainframe designs and putting these features in servers.
An example is the hot-swappable feature that lets administrators
swap components like memory modules, disk drives or CPUs
without switching off the machine.
The battle between Wintel and RISC-based servers continues,
though Wintel systems are fast approaching the speed and
performance of RISC systems.
RISC Vs Wintel
Wintel servers (servers that use Intel processors and the
Windows operating system) are seen as a threat to RISC-based
(Unix) servers. Intel's server processors get more powerful
each year and are fast approaching the performance levels
of RISC-based systems. Wintel servers also cost far less
than Unix servers but analyst say cost alone won't give
Wintel an advantage. This is because manufacturers of RISC-based
processors have proven technologies and well-defined roadmaps.
For intensive processing tasks, IT managers are comfortable
using Unix-based servers that approach mainframe performance.
RISC-based servers continue to hold out with HP, Sun and
others introducing new models. Last year Sun took the lead
in server sales thanks to demand for its Netra servers.
HP recently launched its 9000 Superdome Unix server that
was well received in the market.
But the threat to Unix servers has increased now that Intel
has launched its 64-bit processor, Itanium. Itanium's new
architecture corrects the deficiencies of RISC systems and
has attracted manufacturers of RISC-based/Unix servers.
SGI, NEC and Hitachi already offer Itanium servers pre-loaded
with Linux; HP is porting its HP-UX Unix variant to Itanium
servers manufactured by NEC; Sun has already ported Solaris
to the Itanium platform. IBM has also ported its AIX 5L
(a Unix variant) to Itanium.
Now that Intel has gained support from traditional Unix
server majors, it is only a matter of time before Itanium
processors match mid-range 64-bit RISC servers in performance
and grab market share from RISC servers.
Whether RISC-based or Wintel powered, manufacturers continue
to design servers keeping in mind key business requirements
that were mentioned earlier. Here are a few changes that
we can expect in the next generation of servers that are
already hitting the market.
has always been an issue at server farms and data centers.
The problem was circumvented with the introduction of super
slim rack mounted servers. These servers are just 1.75 inches
thick and are about the size of a pizza box (a form factor
known as 1U). Processing power can be scaled by adding more
servers to a rack. But this calls for additional air-conditioning
and power requirements, making expansion an expensive affair.
Server manufacturers are now contemplating a new design
dubbed 'Ultradense' or 'Blades' a design that packs in more
computing power within the same form factor. Such Bladed
servers come in the form of single boards, one-eighth the
size of a typical 1U (1.75-inch-high) server and consume
up to 12 times less power.
The RLX System 324 (from RLX Technologies) packs in 336
bladed servers in an industry-standard rack currently designed
to house 42 1U servers.
Among the first server manufacturers to roll out Bladed
servers are RLX Technologies, FiberCycle, and Amphus all
use Transmeta's Crusoe processor, which consumes less power
than mainstream PC (IA-32) processors.
But the server heavyweights are not standing by as mere
spectators Compaq, IBM, Dell, HP and Sun are furiously working
on bladed/ultradense designs and are expected to roll out
products by the end of this year. Look out for HP's Powerbar
and Compaq's QuickBlade servers (among others).
Ultradense servers will be targeted at communications companies,
IDCs and ISPs who run data centres packed with servers.
'Big iron' servers are designed for 24x7 operation and should
ideally offer 100 percent uptime. Further, data stored on
servers should be protected against power loss or system
failure. In reality, server components do fail and need
to be replaced with minimal downtime. But servers had to
be powered down for maintenance resulting in downtime, which
affected business. According to the Standish Group, server
failures that lead to downtime can cost companies as much
as $27,000 per minute.
Hence, today's servers are designed with fault-tolerant,
redundant and hot swappable components. Dual processor servers
with hot swappable power supplies, disk drives and memory
modules top an IT manager's shopping list.
The Compaq Proliant L380 and ML370 servers have a backup
memory bank to take over immediately from one that's failed,
letting the defective part be replaced on a more leisurely
schedule. Memory can be upgraded in Compaq's 500 series
of Intel servers without shutting them down. And the 700
series will have memory technology similar to the RAID data-protection
system found on hard-disk arrays.
IT infrastructure must keep up with growing business, which
means processing power, memory and storage on servers should
be scalable. Today, IT managers look for multi-processor
servers-starting with a single or dual-processor system,
and scaling up to several processors.
The HP 9000 Superdome server for instance, can scale up
to 64 CPUs, each operating at 550 MHz. Its memory can scale
up to 128 GB.
Sun's Enterprise 10000 server can scale from 4 to 64 CPUs.
Sun offers a choice of processor clock speeds for this server:
250, 336, or 400 MHz. The memory of this server can range
from 2 GB to 64 GB. There are an array of options for mass
storage, which can scale all the way to 20 terabytes with
the Sun StorEdge A7000 system.
These are single function servers used for dedicated tasks
like Web caching/acceleration, Web hosting, networked attached
storage, load balancing etc. Appliance servers are designed
for quick installation and simple maintenance. These systems
come with a pre-loaded operating system and application
software (often Web server software) that simplifies deployment
so servers can be plugged into networks as easily as desktop
All server majors offer appliance servers: Compaq offers
its TaskSmart series, Sun sells Cobalt Qube servers, Dells
products are called PowerApp, and IBM offers eServer appliances.
When servers are used for mission-critical applications
and businesses depend on them, maximum uptime becomes imperative.
Over the years vendors have been selling fault-tolerant
systems that are largely redundant in nature. But self-healing
and self-monitoring systems look for signs of breakdown
and immediately take corrective action. All this happens
in the background without affecting system performance.
Compaq has been researching and developing self-healing
server technology for years and now IBM is doing the same
through Project eLiza. IBM is investing billions of dollars
into eLiza, which will also extend to storage and other
One facet of eLiza is the 'software rejuvenation' feature
that IBM has incorporated in its xSeries servers. The self-healing
software detects a process called 'aging,' in which abnormalities
build up over time and cause memory errors and consume computer
resources. Special software with artificial intelligence
can sense when a server is about to fail and then shut the
server down systematically, preventing crashes or data loss.
The software closely monitors server activity, determines
the stress the server is under, and will reboot the machine
Soon other server manufactures will be building such features
into servers and there might even be an industry standard
set for self-healing server software.
In the not too distant future, servers will truly be the
powerhouses of network infrastructure, working tirelessly
round the clock and addressing the demands made on network
resources. On the maintenance front, humans will be required
only for physically changing components, as servers will
be able to update their software automatically and heal
Brian Pereira can be reached at firstname.lastname@example.org