port translation for pool member

It's not enough to add the port number to the Host header (in fact you may not even need to do that) - you need select a pool based on the port you want (so you will need 10 pools - one for each port);-

when HTTP_REQUEST { 
    switch [string tolower [HTTP::host]] { 
        "toto.com" { 
            HTTP::header replace Host "[HTTP::host]:22020"
            pool pl_mypool_22020 
        } 
        "titi.com" { 
            HTTP::header replace Host "[HTTP::host]:22021"
            pool pl_mypool_22021 
        } 
        default { 
            drop 
        } 
    } 
}