mike@spock.ucar.edu (Mike Daniels) (09/03/89)
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, -------------------------------------------------------------------------------- Mike Daniels (mike@spock.ucar.edu) RAF/ATD/National Center for Atmospheric Research, Boulder, CO --------------------------------------------------------------------------------
les@chinet.chi.il.us (Leslie Mikesell) (09/04/89)
In article <4206@ncar.ucar.edu> mike@spock.ucar.edu (Mike Daniels) writes: >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? You can get a good idea by running cpio -it to just read the headers back and list the filenames. Unfortunately, the exit status from cpio is not to be trusted, so it may be difficult to automate this. You might try checking for any output to stderr. If you really want to compare the contents of the tape with the filesystem, GNUtar has an option for that. Meanwhile, you might want to locate a copy of the "afio" program that was posted a couple of years ago. It allows you to skip of bad portions of the tape and restart at the next header that it can find. Les Mikesell