Redirect to Multiple URLs

This should work for you.

when RULE_INIT {
  set ::whichone 0
}
when HTTP_REQUEST {
  switch $::whichone {
    0 {
      HTTP::redirect "http://Server1/blah"
    }
    1 { 
      HTTP::redirect "http://Server2/blah" 
    }
  }
  set ::whichone [expr ! $::whichone]
}

Basically it's setting a global variable and toggles it between 0 and 1 on each http request. Then, depending on the current value it issues the appropriate redirect.

Or, you could do the same without the expr command and using a default case to avoid a second comparison on the value 1.

when RULE_INIT {
  set ::whichone 0
}
when HTTP_REQUEST {
  switch $::whichone {
    0 {
      HTTP::redirect "http://Server1/blah"
      set ::whichone 1
    }
    default { 
      HTTP::redirect "http://Server2/blah" 
      set ::whichone 0
    }
  }
}

Hope this helps...

-Joe