dns question

[arson smith]

I have a linux server running dns and would like
to have it switch from one server to another if
one goes down.  basicly have www.x.com point
to x.x.x.21 normaly but if x.x.x.21 goes down then
dns reasings www.x.com to x.x.x.20.  Do I need
to do this in DNS or is there something else I
would need to do this on?  I am not a supper dns
guru so I am not sure where to look.

I am worried about this be cause the x.x.x.21 and
x.x.x.20 are nt boxes (not my choice) but we need the
fail over for them.

Bill Warner
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