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rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
RBD Incremental Backup
======================
This is a simple streaming file format for representing a diff between
two snapshots (or a snapshot and the head) of an RBD image.
Header
doc/dev/rbd-diff: specify that metadata records come before data Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-29 04:19:32 +00:00
~~~~~~
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
Fix formatting of header The header was displaying the newline as a simple "n" due to quoting in the doc. Signed-off-by: Christian Theune <ct@gocept.com>
2014-04-24 07:42:35 +00:00
"rbd diff v1\\n"
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
doc/dev/rbd-diff: specify that metadata records come before data Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-29 04:19:32 +00:00
Metadata records
~~~~~~~~~~~~~~~~
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
doc/dev/rbd-diff: specify that metadata records come before data Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-29 04:19:32 +00:00
Every record has a one byte "tag" that identifies the record type,
followed by some other data.
Metadata records come in the first part of the image. Order is not
important, as long as all the metadata records come before the data
records.
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
From snap
---------
dev/rbd-diff: make formats into bullet lists (solves linebreak probs) Signed-off-by: Dan Mick <dan.mick@inktank.com>
2013-06-05 00:23:52 +00:00
- u8: 'f'
- le32: snap name length
- snap name
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
To snap
-------
dev/rbd-diff: make formats into bullet lists (solves linebreak probs) Signed-off-by: Dan Mick <dan.mick@inktank.com>
2013-06-05 00:23:52 +00:00
- u8: 't'
- le32: snap name length
- snap name
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
Size
----
dev/rbd-diff: make formats into bullet lists (solves linebreak probs) Signed-off-by: Dan Mick <dan.mick@inktank.com>
2013-06-05 00:23:52 +00:00
- u8: 's'
- u64: (ending) image size
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
doc/dev/rbd-diff: specify that metadata records come before data Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-29 04:19:32 +00:00
Data Records
~~~~~~~~~~~~
These records come in the second part of the sequence.
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
Updated data
------------
dev/rbd-diff: make formats into bullet lists (solves linebreak probs) Signed-off-by: Dan Mick <dan.mick@inktank.com>
2013-06-05 00:23:52 +00:00
- u8: 'w'
- le64: offset
- le64: length
- length bytes of actual data
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
Zero data
---------
dev/rbd-diff: make formats into bullet lists (solves linebreak probs) Signed-off-by: Dan Mick <dan.mick@inktank.com>
2013-06-05 00:23:52 +00:00
- u8: 'z'
- le64: offset
- le64: length
rbd: implement 'export-diff' and 'import-diff' commands Export a diff of an image from a previous snapshot to a file (or stdout). Import a diff and apply it to an image, and then create the ending snapshot. Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-26 20:32:28 +00:00
doc/dev/rbd-diff: specify that metadata records come before data Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-29 04:19:32 +00:00
Final Record
~~~~~~~~~~~~
doc/dev/rbd-diff: update incremental file format Signed-off-by: Sage Weil <sage@inktank.com>
2013-03-28 21:19:59 +00:00
End
---
dev/rbd-diff: make formats into bullet lists (solves linebreak probs) Signed-off-by: Dan Mick <dan.mick@inktank.com>
2013-06-05 00:23:52 +00:00
- u8: 'e'