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jakauppila_3997's avatar
jakauppila_3997
Icon for Nimbostratus rankNimbostratus
Jun 13, 2012

Simple HTTP Health Monitor Parsing Issue

Using an HTTP Health Monitor applied on the Application Pool level, I am having an issue.

 

 

My Send String is as follows:

 

 

GET /status.aspx HTTP/1.0\nHost: test.example.com \nConnection: close\n\n

 

 

The Receive String is:

 

 

Status Page

 

 

To my knowledge, the Send String is sent to the Pool Member via IP and what is returned and parsed looking for the Receive String would be raw HTML.

 

 

"Status Page" is present in the title of the page as such:

 

 

Example Status Page

 

 

Is there some issue with a space before the text? As configured as stated here, the monitor marks the pool members as down. If I use other words that are on the page, it works! But I would like to stick to the standard that I have been using so far.

 

 

Let me know if you need any other information.

 

management
monitoring

2 Replies

  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jun 14, 2012
    Hi,

     

     

    Is "Status Page" the exact receive string you're using on the monitor? If you capture a tcpdump filtering for traffic from the static self IP and server IP do you see that exact string in the response?

     

     

    See this page for details on troubleshooting LTM monitors:

     

     

    http://devcentral.f5.com/wiki/AdvDesignConfig.TroubleshootingLtmMonitors.ashx

     

     

    Aaron
  • jakauppila_3997's avatar
    jakauppila_3997
    Icon for Nimbostratus rankNimbostratus
    Jun 14, 2012

    "Status Page" is the exact receive string I'm using.

     

    In the raw HTML coming back, the line containing that string is:

     

    • "[title]Example Status Page[/title]"

    The monitor works fine if I use the following as the receive string:

     

    • [title]
    • Example
    • Status
    • [/title]

    Using the following, the monitor marks the pool members as down:

     

    • Page
    • Page[/title]
    • [title]Example Status Page[/title]

    Is there some issue or conflict in the monitors ability to parse the page coming back?

     

     

     

     

    (Unable to post the HTML tags, so I changed the brackets)