Multiple URL redirect based on incoming URL definition...

Try the solution below.

Additionally, my recommendation would be to uncomment the event disable statements, if there are other iRules attached to VS which are invoking redirects/responses. (Multiple invocations of redirect/response statements are not permitted and will result in a TCL error)

when HTTP_REQUEST {

  set VISITOR "external"

  if { [class match [IP::client_addr] equals "data_ip_internal_networks"] } { 
    set VISITOR "internal"
  }

  if {$VISITOR == "external"} {
    switch [HTTP::host][HTTP::uri] { 
      "qa-myaccess.com/Login/GentivaLinkTest" {
        HTTP::respond 301 location "
        event disable
      }
      "qa-myaccess.gentiva.ghsnet.com/Login/Relias" {
        HTTP::respond 301 location "
        event disable
      }
      default {
        HTTP::respond 301 location "">
        event disable
      } 
    }
  } elseif {$VISITOR == "internal"} {
    switch [HTTP::host][HTTP::uri] {
      "qa-myaccess.com/Login/GentivaLinkTest" {
        HTTP::respond 301 location "
        event disable
      }
      "qa-myaccess.gentiva.ghsnet.com/Login/Relias" {
        HTTP::respond 301 location "
        event disable
      }
      default {
        HTTP::respond 301 location "">
        event disable
      } 
    }
  }
}