[01] HOW OFTEN DO YOU BACKUP YOUR SERVERS?

     Back ups are only made of system software on the fileservers.  If you
     delete a file by mistake, then you're out of luck.  Disk array mirroring,
     parity and striping should, in almost all cases, prevent any data loss
     in the event of a catastrophic single or multiple disk failure. 
     
     Its recommended to use the SDF 'delete, undelete and expunge' utilities
     which you can alias rm to in your .profile.