ENTERPRISE OPERATING SYSTEMS
- By Kevin Jonah
- Apr 26, 1999
The operating system isn’t only the software that runs your computer anymore. In
the typical computer-driven organization today, the operating system on your desktop
computer, notebook PC and server is part of a much larger platform for applications and
data that extends across the LAN and WAN and out onto the Internet.
An OS cannot be an island unto itself—it must work with the rest of the digital
enterprise. Enterprisewide applications require an enterprise operating system.
So what does it take to be an enterprise OS? Some basic requirements common to all
enterprise systems set enterprise OSes apart from ordinary desktop operating systems and
old-fashioned network OSes. A check list of common must-have attributes includes four
things:
Stability. Like that battery-powered rabbit, an enterprise OS has to
keep going and going without a great deal of attention. An enterprise OS should be
multithreaded and multitasking. It should allow for installation of new applications
without a system shutdown and should remain running in the event of an application crash.
A blue screen of death is not an acceptable device for handling application errors.
Most Unix OSes are about as stable as they can be. They rarely require a reboot after
installation of software, and, if applications are designed properly, will rarely
encounter core dumps or system hangs. But that can be a big if.
Microsoft Corp. has done much to make its Windows NT 4.0 more stable over the last few
years, releasing no fewer than four service packs to address issues such as memory leaks.
A fifth, optional service pack is now entering beta testing. And Microsoft has lined up
partners that pledge to work toward 99.9 percent availability for NT. Still, there are
those who question whether NT is ready for bullet-proof solutions.
Novell NetWare 5 has significantly improved NetWare’s stability; it is now
multithreaded. In earlier versions of the NetWare OS, applications that ran on the server
had to be fashioned into NetWare Loadable Modules. The NLM model had some problems,
including occasional incompatibilities between NLMs.
Scalability and high availability. When it comes to the measure of
whether an operating system is truly an enterprise operating system, scalability is the
first hurdle. To handle the demands of large-scale applications, an OS must be able to
scale up to multiple processors in either a symmetric multiprocessing or massively
parallel processing configuration.
SMP is used to balance the processing workload on a system across a number of
processors and is the multiprocessing method usually associated with high-end database and
other enterprise applications. SunSoft Solaris 7, for example, runs SMP on Sun Microsystem
Inc. systems that have as many as 64 processors. Windows NT 4.0 Enterprise Server can run
SMP on up to 32 processors.
Also key to the scalability of applications built on the enterprise OS are high
availability features, such as clustering with failover and load balancing.
Few operating systems support these kinds of features out of the box; most require an
add-on module or other product to provide clustering support, and failover and load
balancing are often dealt with within applications built on these platforms.
If there is an application crash, the true enterprise OS will make provisions for
restarting the application and passing off user sessions to another system, if necessary.
Hewlett-Packard HP-UX and IBM AIX both support clustering through software extensions.
With the SP/3, AIX can scale up to a cluster of 512 nodes. Solaris 7 and Trusted Solaris
2.5.1 both offer clustering through Sun Cluster 2.2, a software extension to the OS that
can cluster up to four systems. Sun Cluster 3.0, the next release, will support up to
eight systems in a cluster.
Compaq Computer Corp.’s NonStop clustering capability, developed for the Tandem
NonStop Unix OS and Himalaya massively parallel servers, is an example of a highly
scalable clustering technology. Compaq has ported NonStop to other operating systems such
as SCO Unix and Windows NT.
Some of NonStop’s clustering technology will be part of the next phase of the
Microsoft Clustering Server technology. Microsoft’s Wolfpack clustering capability,
part of Windows NT Enterprise Server, is essentially limited to shared disk access and
application failover between two servers. Recently, Microsoft introduced true load
balancing for applications running on Microsoft Transaction Server.
To be an enterprise OS, an operating system must provide developers with a framework on
which they can build enterprise-class applications. That framework should include a
component or object architecture—such as Microsoft’s Distributed Component
Object Model (DCOM) or the Object Management Group’s Common Object Request Broker
Architecture (CORBA)—that provides for communication between software components both
on the system running the OS and other systems on the network. It should also provide or
be supported by application servers—database server software, transaction processing
server software and similar software that supports distributed applications.
Sun’s Java Virtual Machine (JVM) technology is available on most versions of the
Unix OS, as are various versions of CORBA frameworks. Microsoft’s Windows NT 4.0
Option Pack includes the Microsoft Transaction Server, a DCOM application server that can
broker connections between remote applications and components running on the server. It
can also support several third-party CORBA object request brokers (ORBs). And NT supports
the JVM, which can be used to support distributed applications based on Enterprise Java
Beans.
Novell NetWare 5 not only supports Java server applications, but it comes with a
built-in Oracle8 database, as does NetWare 4.2. NetWare 5 also comes with a CORBA ORB.
Although most versions of Linux don’t include a JVM, one can be freely downloaded
for most distributions of the OS. There’s also PostgreSQL, a freeware Structured
Query Language database that ships with Linux from Red Hat Software Inc. and can also be
downloaded free. Red Hat Linux also comes with the ORBix CORBA ORB.
Standards support. An enterprise OS should integrate gracefully into a
network. To do so, it should support standard networking, network management and
file-sharing protocols such as the Simple Network Managment Protocol. It also should
integrate with accepted standards for security, directory services and application
services. The rule of thumb: No SNMP, no enterprise OS.
Most products in the accompanying chart offer some form of SNMP as well as TCP/IP
support. TCP/IP has become the standard networking protocol for almost every OS. Even
Novell Inc., long dedicated to its IPX/SPX protocol, offers TCP/IP networking. Microsoft
has made many of its proprietary implementations of networking standards into de facto
standards.
Today, most versions of Unix offer some form of support for file sharing for Windows
network clients, using Microsoft’s Server Message Block and Common Internet
Filesystem protocols. Microsoft supports Network File System file sharing through its NT
Services For Unix add-on to its OS.
A true enterprise OS supports or provides Internet-standard applications such as Web
servers, e-mail servers, File Transfer Protocol servers, Network News servers and others.
It should be able to act as a router, a firewall and Internet proxy, either by itself or
with the aid of additional software.
Most Unix and Unix-like operating systems offer at least basic e-mail support and
support FTP. Solaris 7 comes with a set of services called Easy Access, which includes Sun
Microsystems Inc.’s Web server.
NT includes the Internet Information Server, which includes Web and FTP servers, and a
basic Network News Protocol server. NetWare 4.2 and NetWare 5 both come bundled with
Netscape’s FastTrack Web server.
Enterprise operating systems should also support standard scripting languages.
Scripting languages are key to capturing in the form of utilities the expertise of systems
administrators. They provide administrators with a powerful tool for tasks such as
software distribution, user administration and system configuration.
A good systems administrator can do with scripting and batch languages what would
otherwise require expensive enterprise system management tools—and sometimes even
those tools rely on scripts.
If the Unix and Unix-like operating systems have anything going for them, it’s
scripting languages. Most support some combination of perl, python, bash, csh, ksh,
tcl/tk, ash, awk and sed. Novell supports perl in both NetWare 4.2 and 5, and a language
called NetBasic. NetWare 5 also includes support for Novell’s new Novell Script
language.
Microsoft also supports a version of perl, as well as its own MS-DOS batch script. It
also supports VBScript, a derivative of the Visual Basic language, and Jscript, a clone of
JavaScript, within its browser, though these don’t offer real control over the
operating system.
Remote managability. If you must be physically at the console of a
system to work with it, it isn’t running an enterprise OS. A true enterprise OS can
be administered from a Web browser or a Telnet session, from around the corner or across
the ocean.
It should support remote distribution, installation and configuration of software,
off-site backups and routine maintenance. Sysadmins should not accrue frequent flyer
miles.
The lowest common denominator for remote administration is a Telnet session. When used
in combination with the scripting languages listed above, a good systems administrator can
manage an entire network from a Telnet console.
All flavors of Unix support this text access to an operating system command shell, and
Microsoft now offers a Telnet server as an add-on to Windows NT as part of the NT Services
for Unix pack.
Novell has long offered some form of remote administration, but now it has a remote
graphical user interface.
NetWare 5 offers remote administration through a Java interface. Its ConsoleOne
interface for NetWare 5 gives administrators a way to do system maintenance and
administrative tasks from any Java-capable platform, including Web browsers.
Some operating systems open up administration to a Web browser. Solaris 7 supports
browser-based administration, as does Red Hat Linux.
Additional considerations include security, ease of connectivity and many others. But
if an OS can successfully support the basics listed here, odds are that it will, in one
form or another, support whatever other requirements your organization can throw at it.
The Linux
open-source operating system, of long-time interest to government information technology
professionals and researchers, recently has also been attracting the attention of the
commercial world. And now, with commercial support available, Linux has the look of a
viable option for an enterprise operating system.
Recently, Compaq Computer Corp., Dell Computer Corp., Hewlett-Packard Co. and IBM Corp.
all announced support for various flavors of the Linux OS, and the most common name among
the announcements was Red Hat Software Inc. of Research Triangle Park, N.C. Red Hat is
providing enterprise-level technical support for its distribution of the Linux OS, and IBM
has promised 24-hour global support for any of its customers that use Red
Hat Linux or distributions from Caldera Inc. of Provo, Utah, S.u.S.E. Inc. of Oakland,
Calif., or Pacific Hi-Tech Inc. of Tokyo, the other major distributors of the operating
system.
Recent improvements to Linux have increased its scalability and laid the groundwork for
further advances. Some versions work on symmetric multiprocessing systems with up to 16
processors. Linux has been successfully used in parallel-processing clusters.
Implementations use Linux’s Beowulf clustering technology for supercomputing
applications.
The Energy Department’s Los Alamos National Laboratory’s Theoretical
Astrophysics Group built one such system, called Avalon, from 70 Alpha CPUs. The homegrown
supercomputer’s processing power was as much as 60 billion floating-point operations
per second, said David Neal, Los Alamos systems administrator [GCN, Sept. 7, 1998, Page 43].
Organizations that have Unix systems can use the skills base they already have to
manage Linux systems. Linux supports the Network Information Services, formerly Yellow
Pages, and nearly every common scripting language. Linux also benefits from a variety of
software package management utilities, which can be used to handle installation,
maintenance and software removal.
Red Hat Linux comes with an open-source database server, PostgreSQL, which can be
downloaded free via the Web. There’s also a free Linux port of Sybase Inc.’s
Adaptive Server Enterprise and its Open Client Interface Libraries. Sybase, Oracle Corp.
and IBM Corp. are working on commercial ports of their database servers to the Linux
platform, and Informix Software Inc. of Menlo Park, Calif., has been shipping a Linux
version of its Dynamic Server since last year. On top of that, Informix is also shipping
its Informix-SE database and Informix-4GL development tools—and giving away free
developer licenses for both.
Because Linux supports X Window clients, it can be used to serve up applications to
users with X terminals or other X platforms. GraphOn Corp. of Campbell, Calif., makes
GO-Joe, a Java X client available for Linux servers. GO-Joe lets any browser user run
applications on a Linux system.
But perhaps Linux’s most compelling aspects, from a government IT
professional’s perspective, are that it is essentially free and comes with the
complete source code for the operating system. Patches for problems with Linux are
generally available within days, often hours, of initial bug reports, and can be applied
by recompiling the operating system kernel.
Agencies concerned with the security of their operating systems can check all code for
covert channels and other risks, even modifying the code as desired. Linux’s user
authentication code is modular and can be replaced by other authentication schemes if
desired—that is, if you’ve got enough programmers available. The code and the OS
can be redistributed within an agency with no license fees. All of these factors combine
into a convincing argument for using Linux.
Download Linux free from www.linux.org. The
site will direct you to vendors of the Linux operating system and tools.
Linux is also available for $50, including support, from Red Hat Software. Check Red
Hat’s Web site at www.redhat.com.
Contact Red Hat at 919-547-0012.
Kevin Jonah, a Maryland network manager and free-lance writer, writes often about
computer technology.