Same with Orbit's Backup/3000.


______________________________ Reply Separator _________________________________
Subject: Re: Dat tape usage on MPE
Author:  Cynthia Bridges-Fowler <[log in to unmask]> at HMS-Internet
Date:    4/9/97 1:17 PM


On Tue, 8 Apr 1997 20:58:19 -0600, Johh Pearce <[log in to unmask]> wrote:

> Jim Phillips wrote:
>
>> After Ken Paul's horror story, and Ken Sletten's response, I started
>> thinking about our situation.  All we have is a DDS drive, so we're
>> stuck with using it for backups.  Way back on MPE/V I used the
>
> I, too, was quite comfortable with my nightly DDS backups until reading
> Ken's story.  Now I'm getting concerned.
>
>> VALIDATE program (in TELESUP, IIRC) to validate that a reel-to-reel
>> tape was okay.  But I think it just verified that the tape was readable,
>> it didn't do a bit-by-bit comparison to the corresponding disk files.
>
> My understanding (and I know I'll be corrected if I'm wrong) was VALIDATE
> read the entire tape checking for read errors and also compared checksums
> on the tape to checksums calcuated during the tape read process.
>
>> A quick check of the STORE command reveals no COMPARE option.  The VSTORE
>> command looks like the old VALIDATE (it just "Verifies that the data on
>> a backup media are valid (for example, there are no media errors), and
>> reports errors incurred by STORE when writing the tape.").
>
> You're correct VSTORE does not do a file compare (in a crunch, we'd finish
> backup then let nightly batch jobs start as soon as VSTORE started and
> VSTORE never complained).  With DDS, backup and VSTORE run (unattended) to
> completion before the jobfence is raised to allow users and nightly batch
> jobs to run.
>
> John
>
>---------------------------------------------------------------------------
> John Pearce  <[log in to unmask]>
> Colorado Springs, CO  USA
>

We use RoadRunner. The VALIDATE function reads the entire tape set (takes
as long as a the original backup, too, but can run with other jobs). At
the start of the VALIDATE, it tells how many files and directories are on
the tape, how many files and sectors to be validated, then tells how many
files and sectors were restorable, not just readable.

'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 Cynthia D. Bridges-Fowler             Phone:  1-913 279-2361
 Computer Systems Supervisor
 Kansas City, Kansas Public Library      Fax:  1-913 551-3221
 625 Minnesota Avenue
 Kansas City, Kansas 66101-2805        email:  [log in to unmask]

             All opinions expressed are strictly personal.
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