No delay to client when the primary DNS server goes down?

[nick.seccombe at gmail.com]

Is it possible to get a DNS client to automatically start using its
secondary nameserver when its primary nameserver goes down - the way a
caching-only DNS server dynamically starts using a different forwarder
to avoid repeated timeouts/delays to queries.

All I can think of at present is by reducing the timeout to 1 second in
a client's resolve.conf to reduce the impact, or clustering the DNS
servers.

But a client side configuration would be nice.

Thanks,
Nick