Would this rule cause user problems?

Hi David,

A server hasn't been selected in HTTP_REQUEST so you can't access the server IP in that event. I'd move the HSL::send command to SERVER_CONNECTED and save the values you need for any HTTP request command values to local variables in HTTP_REQUEST.

Here's an example:

when CLIENT_ACCEPTED {
  set hsl_conn [HSL::open -proto UDP -pool syslog-pool]
}
when HTTP_REQUEST {
  set FrontEnd "[IP::client_addr]:[TCP::client_port] <-> [clientside {IP::local_addr}]:[clientside {TCP::local_port}]"
  set Uri [string tolower [HTTP::uri]]
}
when SERVER_CONNECTED {
  set BackEnd  "[IP::local_addr]:[TCP::local_port] <-> [serverside {IP::remote_addr}]:[TCP::server_port]"
  if {$Uri equals "/foobar/foobarweb/login.aspx"} {
    HSL::send $hsl_conn "<190> HSL: FooBar: $FrontEnd | $BackEnd"
  }
  else {
     Log connection details as local7.info; see RFC 3164 Section 4.1.1 - "PRI Part" for more info
    HSL::send $hsl_conn "<190> HSL: $FrontEnd | $BackEnd"
  }
}

Also, you could add logic to your HTTP redirect rewriting rule to handle a null or non-existent host header. You could set some default value if it's not present in the request.

The two iRules should work find on the same virtual server.

Aaron