Web serving
As one of the ways your company faces the world, your Web presence is also becoming indispensable. Downtime can cost money and reputation. What's the best OS to keep things running 24x7?
Kevin McIsaac: The key to selecting an operating system is the recognition that Web servers are best suited to run on a farm of servers not on a large SMP machine in a fail-over cluster.
Web requests are balanced across the farm by the network front-end that ensures both stability and high availability.
The Web server farms should be built from commodity servers, usually 2-way Intel, running a commodity operating system, either Windows 2000 or Linux.
META Group research shows that Fortune 1000 companies have settled on one of three Web server platforms: Microsoft Internet Information Server (IIS) with 47 percent market share, iPlanet Web Server (iWS) with 24 percent market share, and Apache with 18 percent market share.
This research shows a striking affinity between the Web server and the operating system, with approximately 90 percent of Windows 2000 systems running IIS, 96 percent of Linux systems running Apache, and 65 percent of Solaris systems running iWS (with another 25 percent running Apache).
Through 2002, as tight IT budgets favour lower-cost commodity Intel platforms, IIS/Windows 2000 and Apache/Linux will continue to gain market share at the expense of iPlanet Web Server on more expensive Sun/SPARC systems.
Peter Menadue: Scalability is much more than the number or size of processors, and how well OSes scale up to use the infrastructure. It's also about how easy it is to scale applications on top of, or across OS infrastructure, and how manageable that environment is, amongst other things.
In many cases organisations do not utilise the basic scalability of the OS for these reasons. For example, Windows has supported more than four processors for some time, but the vast majority of deployed Windows servers contain four or fewer processors.
The recent spate of security incidents has tempered enthusiasm for Windows-based Web infrastructure, but the combination of Microsoft's security initiatives, a new Windows Server Web edition, and the introduction of blade servers will minimise the drift of Microsoft shops to non-Microsoft platforms.
Dean Thompson: I have serious doubts about IIS for security reasons. Over the last year, a number of security holes have been revealed, and the most serious have allowed outsiders to manipulate files on the server with simple but specially formatted HTTP requests. IIS administrators have found it challenging to keep up with the various security alerts and patches needed to keep their servers safe.
Geoff Halprin: Apache is the single, most proven, scalable, and robust Web serving platform. IIS counters with some custom extensions--FrontPage--and the ability to use ActiveX controls, but each of these has significant security problems.
IIS has proven itself to be insecure beyond repair. The problems with IIS have proven so severe that Gartner Group issued a warning to migrate to Apache or other Web servers. I cannot, in good conscience, recommend a Microsoft platform for Web serving under any circumstances.
Peter Menadue: Solaris has been a comfortable choice for many organisations deploying e-business applications, and it continues as a comfortable choice, particularly as alternative Unixes face a transition to Intel-based platforms.
From a technology perspective, Linux can't be dismissed, but still isn't a prime time choice for enterprise deployments--the services and support infrastructure necessary to underpin an enterprise installation aren't there yet.
Dean Thompson: Web servers are at least as important to organisations as mail servers. But the type of content to be served comes into the decision as well as technical issues such as reliability and security.
Although yet to be treated seriously in some quarters, the content of a Web site can play an important role in the selection of the underlying operating system.
To highlight this point, the advent of the new .NET architecture from Microsoft will force companies that want to provide .NET services or .NET constructed Web pages and possibly even Active Server Pages to use IIS, which will tie them to a Windows 2000 server solution.
In the future this choice will broaden slightly with the introduction of the .NET Server, which is the successor to Windows 2000 Server. Another issue that may force organisations to look at IIS for their Web needs is the architecture used for building Web pages.
A number of products allow organisations to store styles and designs--the "corporate identity," if you will--on a server and to use client programs to build web pages around these styles.
Such systems are normally based on Windows--most notably NT 4 or 2000--and may prefer to operate with IIS or other Windows-based Web servers. Work-arounds may allow their use with Unix-based Web servers, but in some cases tight integration requires Microsoft servers.
I've already mentioned my concerns about IIS security, but if your company requires the ability to provide end users with .NET services or .NET pages, all I can do is strongly recommend that you keep up to date with all of the security advisories and be ready to react quickly to any patches or threats which come out.
I would recommend Solaris 7 or 8, or Linux instead. They are both extremely reliable--an essential characteristic for Web serving--and they provide flexibility in serving Web pages.
Solaris and Linux can run commonly available Web server software (source code included) such as Apache or Tomcat, and they support static HTML, Java Servlet Pages (JSPs), or servlets.
Both platforms also support commercial Web servers such as [BEA's] WebLogic, which can provide deployment flexibility and have the built-in ability to load balance traffic across multiple servers. Similar techniques can be applied to servers such as Apache and Tomcat with the aid of add-on tools.
Solaris and Linux provide mechanisms for performance tuning. Solaris has a number of small configuration files that can be manipulated to effect a change, and once again the Linux source code allows custom optimisations. Linux also provides an interface that allows changes to be made while it is running.
From a security perspective, both platforms must be constantly maintained with security patches to both the Web server and the operating system itself. The difference is that mistakes that previously existed in other Web servers seem to be repeated during the development of IIS.
Geoff Halprin: And Apache wins the scalability stakes hands down. Its closeness to Perl and several derivative development environments (such as Slashcode and Mason) make it easy to churn out Web sites that are capable of the most sophisticated functions.
I find the comments about Unix versions other than Solaris becoming considered "legacy" systems rather funny. I believe it was Solaris that recently announced they would no longer be developing a version for Intel...
Furthermore; the only reason there is an "OS War" is because Microsoft is more interested in making money and increasing their market share than meeting the needs of their customers. Linux is not the one with the "secret" protocols and undocumented "standards."