[CentOS] how to increase DNS reliability?

Hi,

how can DNS reliability, as experienced by clients on the LAN who are
sending queries, be increased?

Would I have to set up some sort of cluster consisting of several
servers all providing DNS services which is reachable under a single
IP address known to the clients?

Just setting up several name servers and making them known to the clients
for the clients to automatically switch isn't a good solution because
the clients take their timeouts and users lacking even the most basic
knowledge inevitably panic when the first name server does not answer
queries.