User`s guide

BACKUP
For each volume that is backed up, /VERIFY validates that volume in a
separate pass immediately after the data is backed up to that volume. The
/VERIFY option compares the original to the backed-up data.
• /RESTORE/VERIFY verifies a data transfer as you are restoring the data.
For each volume that is restored, /RESTORE/VERIFY verifies that volume,
record for record, as it is being restored. Because this verification procedure is
different from /VERIFY and /RESTORE/VERIFY:ONLY, /RESTORE/VERIFY
is less sensitive to position errors (for example, a slight slip in a magtape) than
the other two verification procedures. It simply verifies that each restored
data block can be correctly read.
• /RESTORE/VERIFY:ONLY verifies a data transfer after you back up the
data but before you change or delete the original data.
The /RESTORE/VERIFY:ONLY option compares the backed-up data to the
original. That is, /RESTORE/VERIFY:ONLY first reads the data from the
backed-up volume (as in a RESTORE operation), then reads the original data
and compares the two. It simulates a RESTORE operation except for the
actual restoring of the data.
The /VERIFY:ONLY option is valid only when used with the /RESTORE
option and when the original data is as it was before a backup.
Each verification procedure is alike in that they all:
• Check for device (read) errors.
• Check for data integrity of the blocks read.
The following command line includes the /VERIFY option to perform a post-
backup validation of each output saveset section.
.BACKUP/VERIFY DU0:LGFIL.DAT DU1:
Verification Messages
Depending on the type of verification, when BUP starts the verification process,
BUP displays one of the following messages on the terminal:
?BUP-I-Verify pass started
?BUP-I-Restore/Verify operation started
Again, depending on the type of verification, if the verification is successful, BUP
displays one of the next messages:
?BUP-I-Backup/Verify operation is completed
?BUP-I-Restore/Verify operation is completed
If the output data and the input data differ, BUP displays the error message:
?BUP-F-Verification error <dev:file.type>
26 RT–11 Command Descriptions