The Web Server


The difficult decision of which Web server to use is complicated by many factors. The most important considerations are which operating system you intend to use and which Web server software has the feature set and performance potential to handle your Web site's expectations and traffic load. The following factors might be important when you're selecting a Web server:

  • Operating system

  • Familiarity with the operating system

  • Price

  • Access to support and other resources

  • Ability to host multiple Web sites on a single Web server

  • Log reporting

  • Server-side includes

  • User access security

  • Transaction security

  • Server programming and database support

  • Current equipment (hardware, network, network operating system)

  • Scalability

  • Application server support

  • Management tools

Many factors can affect the performance of a Web server, including the following:

  • The server's processor

  • The type and quantity of RAM on the server

  • The type of bus used for the network adapter card and the disk controller on the server

  • The disk drive's operating characteristics

  • LAN utilization

  • WAN bandwidth

  • The type of content included on Web pages (multimedia versus text)

When an Internet or intranet Web site gets extremely busy, server performance suffers. The first option to improve the situation is to add memory so that more requests can be serviced from the cache. This might not help, though, especially if the server is busy because of background or communication tasks. If that is the case, you have two options: You can purchase a more powerful server and quit using the older one, or you can add individual servers and a load balancer.

Load balancers distribute the incoming requests among a group of Web servers. Load balancing provides the opportunity to utilize your existing resources and then add servers as needed. It also adds fault tolerance: If one server goes down, the others can keep providing service. This fault-tolerance feature also provides uninterrupted service during routine maintenance in which servers need to be offline. A load balancer functions by sitting between the Internet and the Web servers, connected on one side to the Internet router, and to a hub or a switch on the other side. The load balancer uses a virtual IP address to communicate with the router. This address is what is advertised to the Internet for all Web servers, and it masks the actual IP address of the Web server, which aids security. The hub or switch connected to one side of the load balancer is the point of connectivity for all Web servers.



Macromedia ColdFusion MX 7 Certified Developer Study Guide
Macromedia ColdFusion MX 7 Certified Developer Study Guide
ISBN: 0321330110
EAN: 2147483647
Year: 2004
Pages: 389
Authors: Ben Forta

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