The only time I've seen DNS failing after seconds, about six seconds iirc, was when an host had three DNS server configured, all of which were wrong (public DNS

The only time I've seen DNS failing after seconds, about six seconds iirc, was when an host had three DNS server configured, all of which were wrong (public DNS servers, used to query an internal zone). It took seconds for the request to time out because the host tried all three records one after another, and gave up only when all three had failed. But, uh, that's an uncommon situation.