Unix verifying backup program wanted

[Mike Daniels]

Hi.  As an administrator of a MASSCOMP (Concurrent) MC6700 ATT SysVR2
system, I have been given the joyous task of monthly system backups.
I have this process somewhat automated via scripts and cpio, however,
restoring files from certain backup tapes (most notably *long* ones)
sometimes results in the message:

   Out of Phase error -- get help.

and cpio is then aborted at that point on the tape (which means files
after this point are not restorable by cpio).  This error occurs because
the magic number written at the beginning of each cpio record was not
found (a probable tape-write problem).  What I would like is a program
that will *verify* what was written to a backup tape so that I am 
assured of a reasonable backup.  Has anyone written such a program?

Thanks in advance,

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Mike Daniels (mike at spock.ucar.edu)
RAF/ATD/National Center for Atmospheric Research, Boulder, CO
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