Balancing the Web Server Load - Page 2

Web Server Director Pro

With its advanced Layer 7 load balancing features, the Web Server Director Pro appliance is a good choice for larger sites with complex topologies. Version 7.10 now includes Radwares SynApps architecture, which includes health monitoring, traffic redirection, bandwidth management and application security features.

Typical load balancers use Internet Control Message Protocol pings to check server health. Web Server Director Pro goes further by also performing IP and application-level checks. Web page and content verification capabilities allow the load balancer to ensure that Web applications are functioning properly and can use this information to take servers out of service if theyre not.

Traffic redirection allows application-specific servers to be grouped into "superfarms" using a single virtual IP address. When a Web client seeks to access a specific application on a Web site, Web Server Director Pro will send the request to the application server in the right farm. Superfarms make it easy to manage large groups of server farms with servers running different applications.

Web Server Director Pro can also provide TCP port multiplexing, so Web servers with Web pages assigned to different port numbers can be load-balanced to a single IP address.

Web Server Director Pros support for Global Layer 7 traffic redirection allows the system to direct requests to the server farm closest to the requester based on the Layer 7 information contained in the URL. This will improve client response time and is especially valuable for large corporations whose contents are distributed in different data centers across large WANs.

Web Server Director Pro performed well in tests, turning in about 9,800 HTTP requests per second with 4,000 concurrent connections—very close to the maximum of 10,000-requests-per-second limit that can be generated by FlameThrower with four client ports.

The Radware system costs $24,500 and comes in a 1U form factor with eight 10/100M-bps and two optional Gigabit Ethernet ports. Multiple systems can be easily configured and managed through the Web, command-line interface or Radwares Java-based management tool.