I need to set up a Linux box with video monitoring for a small retail business.  I have been looking at ZoneMinder and wanted to know if anyone has used this in the past or has any advice for system hardware and configuration.  The following represents what I am trying to hook up to this new system:

10 cameras - color 
feed from each camera is recorded on HDD or RAID in separate file for each 24 hour period.  
24-hour files are saved for 7 days then are over written with newer feeds.
video feeds will be accessible remotely through web app.

I am concerned with minimum system requirements.  

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James