F5 iRule to reject/allow outbound access based on URI, DNS

If it were me, I'd create a Data Group (class) with the list of hosts that you want to allow www traffic to. I'd then write an iRule that looks like:

when HTTP_REQUEST {
  if {!([class match [HTTP::host] eq myDataGroup])} {
    reject
  }
}

This would prevent any requests bound for anything that's not contained in that data group.

Make sense?

Colin