Dragon mail system is the central mail system for Computer Science Department at Rutgers.  This is a commercial system used by Internet Service Providers called Communigate Pro from Communigate Systems This mail system has been  in production since Spring 2000 and was selected to provide a fast and reliable IMAP based mail server.  

Dragon's mail system has many advanced features that are not common on standard unix mail systems.  For reliability, Dragon mail servers consist of 4 machines: 2 mirror mailservers running as master/slave and 2 spamfilters machines. The mailservers have dual power supplies, dual Uninterupted Power Supplies  and uses 250G of RAID5 SCSI disks . Dragon was designed to minimized down time. In the even of catastophic hardware or software failure on the master machine, the slave machine will automatically become the mail server thus minimizing down time.

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