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bizooga's avatar
bizooga
Icon for Nimbostratus rankNimbostratus
Nov 10, 2015

Name Based Hosting iRule not working

Hi Folks,

My company hosts a bunch of sites on a single virtual server. Each website has its own pool and health monitor. I decided to use this irule to forward the request to the appropriate pool based on the host url.

    when HTTP_REQUEST {
     ABC-DG-Test is a string data-group where the entries are name:value pairs
     name is the requested HTTP host header, value is the associated pool-name

 check the requested HTTP host header against entries in data-group ABC-DG-Test
if { [class match [string tolower [HTTP::host]] equals ABC-DG-Test ] } {
     if the HTTP host header is in ABC-DG-Test
     send the request to the pool associated with the ABC-DG-Test entry
    pool [class match -value [string tolower [HTTP::host]] equals ABC-DG-Test ]
} else {
     drop the request if the host header is not in ABC-DG-Test
    drop
    event disable
    }
    }

The problem is that if the url that comes in is abc.com it will forward to the abc pool. If the url is abc.com/blah it will only display the page for abc.com and not abc.com/blah. The website shows correctly if you hit the web server node.

Any help or suggestions would be appreciated.

Thanks,

Kevin

APM
application delivery
deployment
devops
iRules
LTM
security

3 Replies

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  • Brad_Parker's avatar
    Brad_Parker
    Icon for Cirrus rankCirrus
    Nov 10, 2015

    A.) don't use drop, you are better to use 

    reject
    if you have upstream devices. If your LTM is at the edge then it should be fine.

    2.) Why are you disabling the event? Do you have additional HTTP_REQUEST iRules? Your pool selection should have no effect on the requested URI.

  • VernonWells's avatar
    VernonWells
    Icon for Employee rankEmployee
    Nov 10, 2015

    By the way, if you are using at least 11.4, you may consider using Local Traffic Policies for this:

    If you are using a version before 11.4, Traffic Classes can be used:

    An example of a Local Traffic Policy to direct queries for www.abc.com to pool1 and www.xyz.com to pool2:

    ltm policy policy-hostname-redirect {
    controls { forwarding }
    requires { http }
    rules {
        www.abc.com {
            actions {
                0 {
                    forward
                    select
                    pool pool01
                }
            }
            conditions {
                0 {
                    http-host
                    values { www.abc.com }
                }
            }
            ordinal 1
        }
        www.xyz.com {
            actions {
                0 {
                    forward
                    select
                    pool pool02
                }
            }
            conditions {
                0 {
                    http-host
                    values { www.xyz.com }
                }
            }
            ordinal 2
        }
    }
    strategy first-match
}

    Naturally, this can be done via the Web UI, as well.

  • bizooga's avatar
    bizooga
    Icon for Nimbostratus rankNimbostratus
    Nov 11, 2015

    Hi Guys,

     

    Looks like this is a false alarm. After finally getting a hold of my development team (these websites are custom in house apps), it appears that the application is hard coded to do some redirection. I'm going to try to convince them to stop doing that so my iRule will correctly. Thanks for all your help.