In <199802091551.KAA00799 AT auk.nist DOT gov>, on 02/09/98 at 10:51 AM,
   Michael R Vogt <vogt AT AUK.NIST DOT GOV> said:

>Under the description of the Define Copygorup Frequency parameter,
>the book says "ADSM does not perform an incremental backup unless the
>specified number of days has elapsed since the last backup."

>Does this only apply to scheduled incremental backups, or does it
>also apply to manually run incremental backups?

>If I set FREQ=1, does it simply use 24 hrs as the required elapsed
>time, or does it use some other algorithm?  (If my scheduled backups
>run randomly between 7PM and 7AM, and they happen to run at 1 AM and
>again at 11 PM the same day, will the 11 PM backup do nothing?)

The FREQ parameter affects EACH file at the time it is considered for
backup.  You can run your incrementals as frequently as you wish.

For example, you can set FREQ=1 and schedule (or manually run) and
incremental every 4 hours.  Every time a file is considered for
inclusion in the incremental the following questions are each asked in
turn for each file.  Any negative answer skips the file:

  (1) is the file to be considered?  (include/exclude processing)
  (2) had the file been "changed" from the Active copy on the Server?
  (3) is (current timestamp) minus (timestamp of backup time from
server)
      greater than 24 * FREQ hours?

Assuming that all the questions in turn are answered yes, the file is
copied to the server.

Basically, this parameter translates into English as:

   Take a copy of this file no more than once every X days.

If you (for example) ran incrementals every hour, on the hour, the a
file which was continually being changed would be backed up 24 times a
day (every incremental) if FREQ=0.  When FREQ=1, then one copy would
be made every day.  If FREQ=7, only one copy per week would be made.

Does that help?

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