iRule to redirect http and https to https over port 8888

Updated code with corrections...

when HTTP_REQUEST { 
    if { [HTTP::host] equals "zzzzzz.xyz.com" or [HTTP::host] equals "zzzzzz.xyz.com"} { 
        HTTP::redirect "https://zzzzzz.xyz.com:8888" 
    }
}

What you want is..

when HTTP_REQUEST {
   switch [HTTP::host] {
      "xxxxxx.xyz.com" -
      "yyyyyy.xyz.com" -
      "zzzzzz.xyz.com" { HTTP::redirect https://[HTTP::host]:8888[HTTP::uri] }
   }
}

The "-" means use the action of the following condition. So all of the hosts listed will redirect to same hostname on port 8888.