Load balancing using a DNS server

Access to the Enterprise network server has increased dramatically, a server is difficult to meet the user's access needs, then how to ensure that the user's normal access? There are many solutions, such as using Windows 2000 or Windows Server 2003 to provide Network Load balancing services. However, the settings for this service are very complex. And it is a simple method to realize Network Load Balancing through DNS server.

The author takes the Web server in the enterprise network as an example to introduce how to use the DNS server to achieve Network Load balancing. In order to increase the amount of access to a Web site with a domain name of "www.rtj.net", three Web servers with the same content are deployed in the enterprise network, which provide the same service, but each server has a different IP address. The following sets the DNS servers in the enterprise network to enable the three Web servers to share customer access to the site.

First, enable the loop

For example, in a Windows Server 2003 system, in the DNS server, click the "start → program → admin tools →dns" option, and then go to the DNS Manager window, right-click the DNS server icon, and select the "Properties" option from the shortcut menu that pops up. Then switch to the Advanced tab in the Properties dialog box (Figure 1) to make sure that the Enable looping option is selected in the Server Options list box.

Figure 1

Second, add host records

Create a host record in the Rtj.net area. In the DNS Manager window, right-click the "Rtj.net" Item, select "New Host" in the pop-up menu, enter the new Host dialog box, enter "WWW" in the "Name" field, and enter the IP address of one of the Web servers in the IP address bar, such as 192.168.0.5, and finally click " Add Host button.

Because there are three Web servers in the corporate network and their IP addresses are different, there is also a new two host record with host name "WWW", just like the above, whose IP address is different. This will enable the site domain name to be resolved to separate Web servers.

DNS server rtj.net zone three host records are shown in the following table: