Rewrite Portion of URI

I finally received the list of virtual directories from the development team.

This is what I ultimately used...

Create a new string Data Group containing the legacy URI

ltm data-group legacy_uri
  records {
    /custa/
    /custb/
    /custc/
    ...

iRule

when HTTP_REQUEST
  if { [class match [string tolower [HTTP::uri]] starts_with legacy_uri]} {
  set uri_leg [class match -name -- [string tolower [HTTP::uri]] starts_with legacy_uri]
  set uri_new "/app.web/APPvirtualDirectory/"
  HTTP::uri [string map [list $uri_leg $uri_new] [string tolower [HTTP::uri]]]
  }
}