Before following the steps in this chapter, see Planning for Site Selector. This chapter explains how to create a basic configuration for the Site Selector component of Load Balancer.
Task | Description | Related information |
---|---|---|
Set up the Site Selector machine. | Finding out about the requirements. | Setting up the Site Selector machine |
Set up machines to be load-balanced. | Set up your load balancing configuration. | Step 4. Define load balanced server machines |
To create a basic configuration for the Site Selector component of Load Balancer, there are four basic methods of configuring the Site Selector component:
This is the most direct means of configuring Site Selector. The command parameter values must be entered in English characters. The only exceptions are host names (used, for example, in site name and server commands) and file names.
To start Site Selector from the command line:
You can enter a minimized version of the sscontrol command parameters. You only need to enter the unique letters of the parameters. For example, to get help on the file save command, you can type sscontrol he f instead of sscontrol help file.
To start up the command line interface: issue sscontrol to receive an sscontrol command prompt.
To end the command line interface: issue exit or quit.
The commands for configuring Site Selector can be entered into a configuration script file and run together.
sscontrol file appendload myscript
sscontrol file newload myscript
To save the current configuration into a script file (for example, savescript), run the following command:
sscontrol file save savescript
This command will save the configuration script file in the following directory:
For general instructions and an example of the GUI, see Figure 38.
To start the GUI, follow these steps
In order to configure the Site Selector component from the GUI, you must first select Site Selector in the tree structure. After you connect to a host running ssserver, you can create site names containing servers, start the manager, and start advisors.
The GUI can be used to do anything that you would do with the sscontrol command. For example, to define a site name using the command line, you would enter sscontrol sitename add sitename command. To define a site name from the GUI, right-click Name Server, then in the pop-up menu, left-click Add Site Name. Enter the site name in the pop-up window, then click OK.
Pre-existing Site Selector configuration files can be loaded using the Load New Configuration (for completely replacing the current configuration) and Append to Current Configuration (for updating the current configuration) options presented in the Host pop-up menu. You should save your Site Selector configuration to a file periodically using the Save Configuration File As option also presented in the Host pop-up menu. The File menu located at the top of the GUI will allow you to save your current host connections to a file or restore connections in existing files across all the Load Balancer components.
To run a command from the GUI: highlight the Host node from the GUI tree and select Send command.... from the Host pop-up menu. In the command entry field, type the command that you want to run, for example: nameserver status. The results and history of the commands run in the current session appear in the window provided.
You can access Help by clicking the question mark icon in the upper right corner of the Load Balancer window.
For more information about using the GUI, see Appendix A. GUI: General instructions.
If you are using the configuration wizard, follow these steps:
ssserver
You can launch this wizard from the command prompt by issuing the sswizard. Or, select the Configuration Wizard from the Site Selector component menu as presented in the GUI.
The Site Selector wizard guides you step-by-step through the process of creating a basic configuration for the Site Selector component. It asks you questions about your network and guides you as you setup a site name that enables Site Selector to load balance traffic between a group of servers.
Before setting up the Site Selector machine, you must be the root user (for AIX, HP-UX, Linux, or Solaris systems) or the Administrator (for Windows systems).
You will need an unresolvable fully qualified hostname to use as a site name for a group of servers that you set up. The site name is the name that the clients use to access your site (such as www.yourcompany.com). Site Selector will load-balance traffic for this site name among the group of servers using DNS.
To start the Site Selector server function, type ssserver on the command line.
To start the Name Server, enter the sscontrol nameserver start command.
Optionally, start the Name Server using the bindaddress keyword to bind only to the specified address.
Site Selector will balance the requests sent for the site name to the corresponding servers configured to it.
The site name is an unresolvable host name that the client will request. The site name must be a fully qualified domain name (for example, www.dnsdownload.com). When a client requests this site name, one of the server IP addresses associated with the site name is returned.
To define a site name, issue the following command:
sscontrol sitename add sitename
To set site name options, issue the following command:
sscontrol sitename set sitename option value
For more information, see Command reference for Site Selector.
The server machines are the machines running the applications that you want load balanced. The server is the symbolic name or dotted decimal address of the server machine. To define a server on the site name from step 3, issue the following command:
sscontrol server add sitename:server
You must define more than one server under a site name in order to perform load balancing.
The manager function enhances load balancing. Prior to starting the manager function, ensure that the metric server is installed in all the load-balanced machines.
To start the manager, issue the following command:
sscontrol manager start
The advisors give the manager more information about the ability of the load balanced server machines to respond to requests. An advisor is specific to a protocol. The Load Balancer supplies many advisors. For example, to start the HTTP advisor for a specific site name, issue the following command:
sscontrol advisor start http sitename:port
See Metric Server for information on using system metrics and Metric Server.
If you start advisors, you may modify the proportion of importance given to advisor (port) information being included in the load balancing decisions. To set the site name proportions, issue the sscontrol sitename set sitename proportions command. For more information, see Proportion of importance given to status information.
Use Metric Server with the Site Selector component. Refer to Metric Server for information on setting up Metric Server on all server machines that Site Selector is load balancing.