HTTP rewrite with uri modification

thank you very much so my code should be as below , i will try tomorrow and let you know. also if i want to implement new VIP for old sites with the same pool member do i need to map the vip to the dns and reverse proxy ? or shall i go for SAN certificate

when HTTP_REQUEST {

if { [string tolower [HTTP::host]] contains ".csmcosmos.com" } { 
    set hostname [HTTP::host]
    HTTP::uri "/home.html?u=[HTTP::host][HTTP::uri]" 
    HTTP::header replace Host "aredirector.csmcosmos.com" 
} 

}

when HTTP_RESPONSE {

if { [info exists hostname] } {
    HTTP::header replace Host $hostname
}

}