Lines Matching full:to
15 be used to manipulate disk image chains to accomplish certain tasks,
19 to another target image; and point-in-time (and incremental) backups of
21 primitives, and some (non-exhaustive list of) examples to illustrate
50 [B]. And live QEMU is currently writing to image [B], consequently, it
51 is also referred to as the "active layer".
53 There are two kinds of terminology that are common when referring to
57 above, image [A] can be referred to as 'base', and image [B] as
63 to as the backing file, and image [B] as overlay.
82 .. note:: Once the 'stream' operation has finished, three things to
85 (a) QEMU rewrites the backing chain to remove
86 reference to the now-streamed and redundant backing
103 things to note here as well:
105 (a) QEMU rewrites the backing chain to remove reference
106 to now-redundant overlay images that have been
110 -- it ought to be manually removed;
119 disk to another image.
122 Point-in-time (live) copy of a block device to a destination.
130 To show some example invocations of command-line, we will use the
144 parameter that is used to refer to the disk image a.qcow2 ('node-A') --
145 this is a cleaner way to refer to a disk image (as opposed to referring
146 to it by spelling out file paths). So, we will continue to designate a
147 ``node-name`` to each further disk image created (either via
149 image chain, and continue to refer to the disks using their
154 To interact with the QEMU instance launched above, we will use the
164 In the event we have to repeat a certain QMP command, we will: for
181 writing to it. (The rule of thumb is: live QEMU will always be pointing
182 to the rightmost image in a disk image chain.)
200 Here, "node-A" is the name QEMU internally uses to refer to the base
204 To create the rest of the overlay images, [C], and [D] (omitting the raw
238 The ``block-stream`` command allows you to do live copy data from backing
254 into it (where live QEMU writes go to)::
263 backing file pointer of image [D] will be adjusted to point to image
272 images, it is possible to copy contents from image [B] into image
275 adjusted to point to [A]. I.e. after performing "intermediate
277 live QEMU is writing to [D])::
285 For `Case-1`_, to merge contents of all the backing files into the
300 image [D] ends up referring to image [A] as its backing file::
305 images [B] into [C], where [C] ends up referring to [A] as its backing
322 and can now be (optionally) discarded, or retained to create further
332 commit" (i.e. it is possible to merge the "active layer", the right-most
333 image in a disk image chain where live QEMU will be writing to, into the
334 base image). This is analogous to ``block-stream``, but in the opposite
338 QEMU is writing to the right-most image in the chain, [D]::
347 chain is the following, where image [C] is adjusted to point at [A]
353 resulting chain, where image [D] is adjusted to point to image [A]
380 For :ref:`Case-1 <block-commit_Case-1>`, to merge contents only from
397 to point to image [A], and the original 4-image chain will end up being
398 transformed to::
427 The following is the flow for :ref:`Case-3 <block-commit_Case-3>` to
437 the active layer, [D], is committed back to [A] -- which is where live
458 We can see the 'commit' job is now ready to be completed, as indicated
506 Synchronize a running disk image chain (all or part of it) to a target
514 allows you to copy data from the entire chain into a single target image
525 changes to ``BLOCK_JOB_COMPLETED``.
532 So there are two possible actions to take, after a 'mirror' job has
545 QEMU) to point to the target image, [E], causing all the new writes
546 from this point on to happen there.
549 *which* part of the disk image chain will be copied to the target.
552 (1) ``full`` -- Synchronize the content of entire disk image chain to
556 in the chain to the target
564 overwritten by the guest is first copied out to the
566 from start to end. With ``sync=none``, it's only the
573 Refer to the :doc:`bitmaps` document in the QEMU source
574 tree to learn about the detailed workings of the ``incremental``
581 To copy the contents of the entire disk image chain, from [A] all the
582 way to [D], to a new target (``drive-mirror`` will create the destination
597 to the destination.
600 'mirror' job is "ready" to be completed (and QEMU will also emit an
630 content from the entire chain, [A] to [D])::
640 (b) Or, complete the operation and pivot the live QEMU to the target
669 contents of the *top*-most disk image (i.e. the active layer), [D], to a
678 Sometimes, this is also referred to as "shallow copy" -- because only
679 the "active layer", and not the rest of the image chain, is copied to
687 chain -- from images [A] to [C] -- are already expected to exist in some
690 ``Contents-of-A-B-C.qcow2`` as its backing file), to which the contents
691 of image [D] (from the source QEMU) will be mirrored to::
750 synchronize to a pre-created file, therefore 'existing', file on the
767 event ``BLOCK_JOB_READY`` is emitted, issue ``block-job-cancel`` to
798 migrations to localhost for other reasons).
804 The ``blockdev-mirror`` command is equivalent in core functionality to
807 Also: for ``blockdev-mirror``, the 'target' image needs to be explicitly
808 created (using ``qemu-img``) and attach it to live QEMU via
809 ``blockdev-add``, which assigns a name to the to-be created target node.
811 E.g. the sequence of actions to create a point-in-time backup of an
812 entire disk image chain, to a target, using ``blockdev-mirror`` would be:
814 (0) Create the QCOW2 overlays, to arrive at a backing chain of desired
820 ``blockdev-add`` to QEMU
822 (3) Perform ``blockdev-mirror`` (use ``"sync": "full"`` to copy the
823 entire chain to the target). And notice the event
827 job ready to be completed
847 To copy the contents of the entire disk image chain, from [A] all the
848 way to [D], to a new target, call it [E]. The following is the flow.
860 Add the above created target image to QEMU, via ``blockdev-add``::
938 you to create a point-in-time snapshot.
954 To create a target image [E], with content populated from image [A] to
974 Moving from the deprecated ``drive-backup`` to newer ``blockdev-backup``
982 ``format`` arguments which don't apply to an existing block node. See
992 E.g. the sequence of actions to create a point-in-time backup
993 of an entire disk image chain, to a target, using ``blockdev-backup``
996 (0) Create the QCOW2 overlays, to arrive at a backing chain of desired
1002 ``blockdev-add`` to QEMU
1004 (3) Perform ``blockdev-backup`` (use ``"sync": "full"`` to copy the
1005 entire chain to the target). And notice the event
1022 overlay (live QEMU is writing to it)::
1026 The following is the procedure to copy the content from the entire chain
1027 to a target image (say, [E]), which has the full content from [A] and
1048 Then add it to QEMU via ``blockdev-add``::
1063 Then invoke ``blockdev-backup`` to copy the contents from the entire
1064 image chain, consisting of images [A] and [B] to the target image
1102 to get shared "write" lock on e.qcow2", will be thrown when you do
1103 ``qemu-img compare`` to verify the integrity of the disk image
1112 One way to confirm the backup disk image contains the identical content
1113 with the disk image chain is to compare the backup and the contents of