13.4 Validation Operations

To ensure the integrity of the backup data, MySQL Enterprise Backup provides a validate command for validating a backup by the checksum values of its data pages after the backup is created or transferred to another system.

mysqlbackup [STD-OPTIONS]
             [--backup-dir=PATH][--backup-image=IMAGE] 
            [MESSAGE-LOGGING-OPTIONS]
            [PROGRESS-REPORT-OPTIONS]
            [CLOUD-STORAGE-OPTIONS]
            validate

• validate

  Verifies that a backup is not corrupted, truncated, or damaged. This operation validates the checksum value for each data page in a backup.

  To avoid spending excessive time and resources on files that are too heavily corrupted, mysqlbackup stops validating a .ibd file after more than twenty corrupted pages are found in it, and proceeds to the next file instead. In that case, the operation's summary will not give a full count of corrupted pages, but only says “at least 20 pages are corrupted.”

  The operation also has the following limitations:

  • For any backup directory, the operation can only validate the InnoDB data files (ibdata* and *.ibd files) in it. Problems with other file types within a backup directory (for example, .frm file corruptions) are not detected.

  • If any .ibd or .frm files are missing from a backup directory during a backup or have been deleted from a backup directory after the backup was made, the validate operation will not be able to detect the problem.

  • If a backup directory has been corrupted by removing or truncating pages from any of the .ibd files inside , the validate operation will not be able to detect the problem.

  Here is a sample command for validating a backup directory:

  mysqlbackup -uroot --backup-dir=/logs/backupext validate

  Here is a sample command for validating a backup image:

  mysqlbackup -uroot --backup-image=/logs/fullimage.mi  validate

  The following is a sample command for validating an encrypted backup image and the output for the successful validation:

  $ mysqlbackup –backup-image=/meb/backups/image.mbi --decrypt --key-file=/meb/enckeyfile validate
  
  140219 11:22:44 mysqlbackup: INFO: Validating image ... /logs/img.bi
  140219 11:22:44 mysqlbackup: INFO: Validate: [Dir]: meta
  140219 11:22:45 mysqlbackup: INFO: Total files as specified in image: 44
  mysqlbackup: INFO: datadir/tpch/tabnorm7.ibd Validated...
  mysqlbackup: INFO: datadir/tpch/tabnorm8.ibd Validated...
  mysqlbackup: INFO: datadir/tpch/tabnorm9.ibd Validated...
  ................
  140219 11:22:45 mysqlbackup: INFO: Validate operation completed successfully.
  140219 11:22:45 mysqlbackup: INFO: Backup Image validation successful.
  mysqlbackup: INFO: Source Image Path = /logs/img.bi
  mysqlbackup completed OK!

  This is a sample output for a checksum mismatch in the header:

  mysqlbackup: ERROR: Checksum mismatch.
  Computed checksum: ###          Checksum in image: ### mysqlbackup:    ERROR: Problem verifying checksum of initial header of backup image.
  Image Path = /meb/backups/image.mbi
  mysqlbackup: ERROR: Backup image validation failed.

  This is a sample output for an image containing corrupted .ibd files:

  mysqlbackup: ERROR: datadir/db2/bigtab1.ibd has corrupt page number : 64   page number from page header : 64
  mysqlbackup: ERROR: datadir/db2/bigtab1.ibd is corrupt and has : 10 corrupt pages
  mysqlbackup: ERROR: datadir/db2/t1.ibd has corrupt page number : 4   page number from     page header : 0
  .......
  mysqlbackup: ERROR: datadir/db2/t1.ibd is corrupt and has : 5 corrupt pages
  mysqlbackup: ERROR: datadir/ibdata1 has corrupt page number : 63   page number from page header : 63
  mysqlbackup: ERROR: datadir/ibdata1 has corrupt page number : 7   page number from page header : 7
  ..........
  mysqlbackup: ERROR: datadir/ibdata1 is corrupt and has : 10 corrupt pages
  mysqlbackup failed with errors!

  This is a sample output for a successful validation for a compressed backup directory

  mysqlbackup: INFO: /backups/backup-dir/datadir/tpch/tabnorm5.ibz Validated...
  mysqlbackup: INFO: /backups/backup-dir/datadir/tpch/tabnorm6.ibz Validated...
  mysqlbackup: INFO: /backups/backup-dir/datadir/tpch/tabnorm7.ibz Validated...
  mysqlbackup: INFO: /backups/backup-dir/datadir/tpch/tabnorm8.ibz Validated...
  mysqlbackup: INFO: /backups/backup-dir/datadir/tpch/tabnorm9.ibz Validated...
  mysqlbackup: INFO: /backups/backup-dir/datadir/tpch/tabrowformat.ibz Validated...
  140219 11:22:45 mysqlbackup: INFO: Validate backup directory operation completed successfully.