Lines Matching full:backup
9 Dirty Bitmaps and Incremental Backup
14 incremental or differential backup regimens.
21 backup features to management applications, or power users who run and
126 modifying a bitmap, and happens when the bitmap is being used for a backup
276 - An incremental backup created from an empty bitmap will copy no data, as if
341 differential backup windows.
493 #. Create a full drive backup of drive0.
499 At this point, the bitmap and drive backup would be correctly in sync, and
501 the full drive backup.
511 - Create a full drive backup of ``drive0``.
516 drive backup, incremental backups can still be authored from this
518 occurred prior to the backup operation. Transactions allow us to
538 other partial disk images on top of a base image to reconstruct a full backup
539 from the point in time at which the incremental backup was issued.
542 blocks out to a destination. We will be using the `blockdev-backup
550 Example: New Incremental Backup Anchor Point
554 create a new incremental backup chain attached to a drive.
556 This example creates a new, full backup of "drive0" and accompanies it with a
564 the backup job runs, will be written locally and not to the backup
582 "type": "blockdev-backup",
613 "type": "backup",
649 Example: Resetting an Incremental Backup Anchor Point
652 If we want to start a new backup chain with an existing bitmap, we can also
653 use a transaction to reset the bitmap while making a new full backup:
669 "type": "blockdev-backup",
688 "type": "backup",
706 Example: First Incremental Backup
709 #. Create a full backup and sync it to a dirty bitmap using any method:
711 - Either of the two live backup method demonstrated above,
719 - The full backup is named ``drive0.full.qcow2``.
722 #. Create a destination image for the incremental backup that utilizes the
723 full backup as a backing image.
750 #. Issue an incremental backup command:
755 "execute": "blockdev-backup",
772 "type": "backup",
782 This copies any blocks modified since the full backup was created into the
785 reflect the "incremental" backup regimen, which only copies out new changes
786 from each incremental backup.
788 .. note:: Any new writes that occur after the backup operation starts do not
789 get copied to the destination. The backup's "point in time" is when
790 the backup starts, not when it ends. These writes are recorded in a
791 special bitmap that gets re-added to bitmap0 when the backup ends so
792 that the next incremental backup can copy them out.
794 Example: Second Incremental Backup
797 #. Create a new destination image for the incremental backup that points to
823 #. Issue a new incremental backup command. The only difference here is that we
829 "execute": "blockdev-backup",
846 "type": "backup",
856 Because the first incremental backup from the previous example completed
858 we use ``bitmap0`` again to create a new incremental backup that targets the
869 Each new incremental backup re-synchronizes the bitmap to the latest backup
875 a full image. The dependency terminates with each full backup.
877 Each backup in this chain remains independent, and is unchanged by new entries
879 valid backup of the disk as it was when that backup was issued.
884 Backup images are best kept off-site, so we often will not have the preceding
885 backups in a chain available to link against. This is not a problem at backup
898 backup commands to have QEMU create an image without a backing
920 #. Issue a new incremental backup command. Apart from the new destination
926 "execute": "blockdev-backup",
943 "type": "backup",
954 set the backing image when attempting to restore the backup:
968 Example: Multi-drive Incremental Backup
1014 #. Create a full (anchor) backup for each drive, with accompanying bitmaps:
1037 "type": "blockdev-backup",
1045 "type": "blockdev-backup",
1064 "type": "backup",
1078 "type": "backup",
1130 #. Issue a multi-drive incremental push backup transaction:
1139 "type": "blockev-backup",
1148 "type": "blockdev-backup",
1168 "type": "backup",
1182 "type": "backup",
1192 Push Backup Errors & Recovery
1195 In the event of an error that occurs after a push backup job is successfully
1209 against is kept at the issuance of the last successful incremental backup,
1210 instead of being moved forward to the start of this now-failed backup.
1213 on the destination), the incremental backup command can be retried with the
1219 Incremental Push Backup jobs that fail individually behave simply as
1247 #. Attempt to create an incremental backup via QMP:
1252 "execute": "blockdev-backup",
1285 "type": "backup"
1330 freeing up space on the backup volume:
1335 "execute": "blockdev-backup",
1354 "type": "backup",
1365 QMP commands like `blockdev-backup
1374 a management application may have to deal with a partial backup failure after
1377 If multiple backup jobs are specified in a single transaction, if one of those
1378 jobs fails, it will not interact with the other backup jobs in any way by
1384 This example illustrates a transaction with two backup jobs, where one fails
1387 #. Issue the transaction to start a backup of both drives.
1396 "type": "blockdev-backup",
1405 "type": "blockdev-backup",
1431 "type": "backup",
1463 "type": "backup"
1470 deleted. If a VM-wide incremental backup of all drives at a point-in-time is
1472 account that a new incremental backup for drive0 needs to be based on top of
1475 For this example, an incremental backup for ``drive0`` was created, but not
1476 for ``drive1``. The last VM-wide crash-consistent backup that is available in
1477 this case is the full backup:
1484 To repair this, issue a new incremental backup across both drives. The result
1485 will be backup chains that resemble the following:
1507 Regardless of if a participating incremental backup job failed or was
1511 Here's the same multi-drive backup scenario from `Example: Partial
1515 #. Issue the multi-drive incremental backup transaction:
1527 "type": "blockdev-backup",
1536 "type": "blockdev-backup",
1553 #. Receive notification that the backup job for ``drive1`` has failed:
1575 "type": "backup"
1588 "type": "backup",