  Data reliability, defragmentation, shadowing? 
 The Question is:
 
Hello!
 
I'm using DEC File Optimizer for VMS DFG V1.0 on
VAX 3100 running VMS v5.5-2.
 
How reliable is it? I mean if electricity goes out or my machine crashes
during defragmentation
process, will I lose data?
 
                       Tank you very much,
 
                                 Borut
 
 The Answer is:
 
  There can be no certain or single answer to open-ended questions,
  and particularly those involving the potential implications of
  unspecified electrical problems or random glitches.
 
  As has been the case elsewhere, the OpenVMS Wizard would recommend
  various upgrades -- both your DFO and OpenVMS versions are rather
  old.  The Wizard would particularly recommend upgrading DFO to the
  V2.3 release or (if/when available) later.
 
  The curmudgeonly Wizard generally prefers to use offline means for
  disk defragmentation -- BACKUP with verify to archival media and
  a subsequent restoration -- but even this reliable method has
  occasionally failed the Wizard.  (These were hardware failures.)
 
  The Wizard has also seen the results of electrical problems and
  even lightning strikes, and the defragmentation tool would tend to
  be low on your priorities.
 
  Current online defragmentations tools such as DFO are reliable and
  are particularly applicable in those environments that cannot afford
  or tolerate the required downtime, or cannot afford the labor involved
  with performing the offline defragmentation technique.
 
  If you are particularly concerned around reliability and uptime, you
  will want to contact your Compaq reseller or Compaq presales support
  for information on shadowing, UPS and power protection options,
  StorageWorks batteries, consulting services, and other options.
 
  The Wizard would recommend periodic BACKUP of your data, regardless
  of the use of shadowing or defragmentation tools -- neither of these
  tools will protect against catastrophic failures, fires, application
  failures, or accidental or intentional data deletions.
 
