Configuring the HTTP or HTTPS advisor

You can configure the HTTP or HTTPS advisor by using the request and response (URL) option. The URL option for the HTTP or HTTPS advisor is available for the Dispatcher and CBR components.

After you start an HTTP or HTTPS advisor, you can define a unique client HTTP URL string, specific for the service that you want to query on the server.

The HTTP or HTTPS advisor uses the advisorrequest string to query the health of the servers. The default value is HEAD / HTTP/1.0. The advisorresponse string is the response that the advisor scans for in the HTTP response. The advisor uses the advisorresponse string to compare to the real response that is received from the server. The default value is null.

Important: If a blank is contained within the HTTP URL string:

When you issue the command from the dscontrol>> shell prompt, you must place quotes around the string if a blank is contained within the string. For example:
```
server set cluster@port@server advisorrequest "head / http/1.0"
server set cluster@port@server advisorresponse "HTTP 200 OK" 
```

When you issue the dscontrol command from the operating system prompt, you must precede the text with "\" and follow the text with \"". For example:

dscontrol server set cluster@port@server
advisorrequest "\"head / http/1.0\""

dscontrol server set cluster@port@server advisorresponse "\"HTTP 200 OK\""

When you create the request that the HTTP or HTTPS advisor sends to backend servers to see whether they are functioning, you type the start of the HTTP request and Load Balancer completes the end of the request with the following:

\r\nAccept:
*/*\r\nUser-Agent:IBM_Load_Balanacer_HTTP_Advisor\r\n\r\n

If you want to add other HTTP header fields before Load Balancer appends this string to the end of the request, you can do so by including your own \r\n string in the request. The following example is what you might type to add the HTTP host header field to your request:

GET /pub/WWW/TheProject.html HTTP/1.0 \r\nHost: www.w3.org

Note: After you start an HTTP or HTTPS advisor for a specified HTTP port number, the advisor request and response value is enabled for servers under that HTTP port.