Progress
Database Administration
Guide and Reference
Verifying a Backup
Immediately after backing up the database, verify that the backup does not contain any corrupted blocks. Use the Progress Restore utility to verify the integrity of a full or incremental backup of a database as follows:
- Run the Progress Restore utility with the Partial Verify (-
vp
) parameter. With this parameter, Progress checks the backup for bad blocks and reports whether any exist.- Run the Progress Restore utility with the Full Verify (-
vf
) parameter. With this parameter, Progress compares the backup to the database block-for-block.These parameters do not actually restore the database. They only verify the status of the backup, notify you if there are any bad blocks, and report whether the blocks are recoverable. You must run the restore utility again (without the partial or full verify parameters) to restore the database.
When you use the -
vp
parameter, PROREST scans the backup and recalculates the CRC code for each block. It then compares the newly calculated CRC code with the CRC code stored in the block header. If the codes do not match, Progress marks the block as bad and displays the following message:
If the backup contains error-correction blocks and a redundancy set contains only one bad block, PROBKUP uses the error-correction block (and the other blocks in the redundancy set) to re-create the bad block. The error-correction block is the EXCLUSIVE OR of the backup blocks in the redundancy set. When Progress recovers the block, the following message appears:
If the redundancy set contains more than one bad block or if the backup does not include error-correction blocks, Progress cannot recover the bad block and displays the following message:
Progress also cannot recover a corrupted block if the error-correction block itself has a CRC check failure. In this case, the following message appears:
If Progress encounters 10 unrecoverable errors during the verify pass or during the database restore, you can terminate the verify operation:
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