Windows 2003 hosting

Written by: Peter Todorov

Windows 2003 Server is the latest Microsoft server operating system. The OS was released in the beginning of 2003 and comes in 4 different editions:

Standard Edition
Enterprise Edition
Datacenter Edition
Web Edition

We will talk about only 2 of the Windows 2003 editions as they are most widely used as OS for web hosting. These 2 editions are the Web Edition and the Standard Edition. The Windows 2003 Server Web Edition is the lightest version of the OS, designed specifically for use as a hosting platform. It can have maximum of 2GB RAM. In contrast the Windows 2003 Server Standard Edition can have up to 4GB RAM. Both editions come with full MS .NET Framework support (including ASP.NET support) and fully functional IIS 6.0. You can administer either of the Windows 2003 Server editions with Remote Desktop. One of the shortfalls of the Windows 2003 Server Web Edition is that you cannot run MS SQL Server database on it. You can run SQL Server on the Standard Edition, which makes it a better choice for hosting platform.

Internet Information Services 6.0 – The Windows 2003 web server

Internet Information Services (IIS) 6.0 is the web server that comes with all versions of Microsoft Windows Server 2003. Compared to its predecessors (IIS 5, IIS 4, IIS 3) IIS 6 is more reliable, easier to manage, more scalable, and much more secure. IIS 6.0 provides a platform for building applications with ASP.NET and Microsoft .NET Framework as well as with classic ASP. IIS 6.0 has been completely redesigned to increase web server reliability.

IIS 6.0 Reliability

The new, fault-tolerant process architecture of IIS 6.0 allows isolating web applications into independent units called application pools. Errors in one of the application pools won’t affect the rest of the application pools running on the same web server and the web server itself, thus increasing the IIS 6.0 reliability.

Another new feature is the application pool health monitoring. IIS 6.0 periodically checks the status of an application pool and automatically restarts it on failure of the web sites and applications within that application pool, increasing the application uptime.

IIS 6.0 will automatically stop and restart faulty web sites and applications based on a flexible criteria set, including CPU and memory usage. This new feature is known as a process recycling. IIS 6.0 also maintains the client TCP/IP connection while a worker process is being recycled.

If a web application fails frequently within a short amount of time, IIS 6.0 will automatically disable it and return a "503 Service Unavailable" error message to any requests for this application. This feature called rapid-fail protection can be used to protect a web server against DDOS (denial of service) attacks.

These 4 features increase the overall uptime and reliability of the web applications running on IIS 6.0.

IIS 6.0 Security

IIS 6.0 security has been significantly improved compared to the previous versions of the web server.

Locked-down web server
IIS 6.0 is not installed by default on Windows Server 2003. Even after you installed it, IIS 6.0 will serve only static content. Web server administrators can enable/disable various IIS features.

Web service extensions list
The default installation of IIS will not serve files with dynamic extensions. If you want your IIS 6.0 serving dynamic files like ASP, ASP.NET or PHP you must add the appropriate extension to the Web service extensions list. This prerequisite stops anyone from calling a web page with a dynamic extension that has not been enabled. IIS 6.0 will return a 404 error to all requests for dynamic content which extensions are not enabled.

Default low-privilege account
By default all IIS 6.0 worker processes run as Network Service user accounts. Network Service account is a new account type with limited privileges, on Windows Server 2003. All ASP built-in functions always run as low-privileged accounts (anonymous user).

Conclusion

After the success of Windows 2000 Server as a stable and reliable hosting environment, the Windows 2003 Server is the next MS OS, which will have a big impact on the hosting market. With Windows 2003 Server Microsoft are becoming a major player in the today’s hosting industry. According to the Netcraft’s Web Server Survey from January 2004 (http://news.netcraft.com/archives/web_server_survey.html) Windows OS has 21% of the hosting market, while Apache web server has 67% market share.