How does squid 2 handle a failed cache_dir?

Was wondering how squid will handle a cache_dir failing?

ie, if we have 6 drives, each mounted individually and listed as cache_dir
's and one fails, does the whole cache become corrupt? Or will replacing
that one drive result in loosing the cache data on that drive only?

Installing a RAID system at the hardware level is the other option, but
the problem with hardware raid (say raid 5) is that it is hard to expand
the raid set if need be... if squid will handle a cache_dir dissapearing
gracefully then spanning multiple disks for a large chache will be a no
brainer.

Regards,

Mikel

-- 
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Mikel Lindsaar        |  "The dream is the foundation,
mikel@cynet.net.au    |        of our society!" 
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Cynet!  The Business ISP!        http://www.cynet.net.au/
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