Question re separating caching and authoritative servers

[John Wobus]

What are the good ways to let your local caching server serve your
own site's data even after a caching-server reboot during an Internet
outage? If the caching server locates your own authoritative data
through normal delgation channels, and cannot reach the roots and
TLDs, then your own local clients could be unable to resolve names
of local servers, etc.

Any especially good or bad practices? Things that have worked well
or poorly? Right now, I'm leaning toward having the caching server
transfer key zones.

John Wobus