mirror of
https://github.com/ceph/ceph-csi.git
synced 2024-12-23 21:40:20 +00:00
doc: add document for rbd snapshot and clone
Added a document which contains the steps and RBD CLI commands we execute when we create a kubernetes snapshot, delete kubernetes snapshot, Restore a snapshot to a new PVC,Kubernetes volume cloning and kubernetes PVC deletion. Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
This commit is contained in:
Madhu Rajanna
mergify[bot]
parent
be8d3b6047
commit
cf98442ef6
154
docs/design/proposals/rbd-snap-clone.md
Normal file
154
docs/design/proposals/rbd-snap-clone.md
Normal file
@ -0,0 +1,154 @@
|
||||
# Steps and RBD CLI commands for RBD snapshot and clone operations
|
||||
|
||||
- [Steps and RBD CLI commands for RBD snapshot and clone operations](#steps-and-rbd-cli-commands-for-rbd-snapshot-and-clone-operations)
|
||||
- [Create a snapshot from PVC](#create-a-snapshot-from-pvc)
|
||||
- [steps to creating a snapshot](#steps-to-creating-a-snapshot)
|
||||
- [RBD CLI commands to create snapshot](#rbd-cli-commands-to-create-snapshot)
|
||||
- [Create PVC from a snapshot (datasource snapshot)](#create-pvc-from-a-snapshot-datasource-snapshot)
|
||||
- [steps to create a pvc from snapshot](#steps-to-create-a-pvc-from-snapshot)
|
||||
- [RBD CLI commands to create clone from snapshot](#rbd-cli-commands-to-create-clone-from-snapshot)
|
||||
- [Delete a snapshot](#delete-a-snapshot)
|
||||
- [steps to delete a snapshot](#steps-to-delete-a-snapshot)
|
||||
- [RBD CLI commands to delete a snapshot](#rbd-cli-commands-to-delete-a-snapshot)
|
||||
- [Delete a Volume (PVC)](#delete-a-volume-pvc)
|
||||
- [steps to delete a volume](#steps-to-delete-a-volume)
|
||||
- [RBD CLI commands to delete a volume](#rbd-cli-commands-to-delete-a-volume)
|
||||
- [Volume cloning (datasource pvc)](#volume-cloning-datasource-pvc)
|
||||
- [steps to create a Volume from Volume](#steps-to-create-a-volume-from-volume)
|
||||
- [RBD CLI commands to create a Volume from Volume](#rbd-cli-commands-to-create-a-volume-from-volume)
|
||||
|
||||
This document outlines the command used to create RBD snapshot, delete RBD
|
||||
snapshot Restore RBD snapshot and Create New RBD image from RBD image.
|
||||
|
||||
## Create a snapshot from PVC
|
||||
|
||||
Refer [snapshot](https://kubernetes.io/docs/concepts/storage/volume-snapshots/)
|
||||
for more information realted to Volume cloning in kubernetes.
|
||||
|
||||
### steps to creating a snapshot
|
||||
|
||||
- Check if the parent image has more snapshots than the configured value, if
|
||||
its has more snapshot Add tasks to flatten all the temporary cloned images
|
||||
and return ResourceExhausted error message
|
||||
- Create a temporary snapshot from the parent image
|
||||
- Clone a new image from a temporary snapshot with options
|
||||
--rbd-default-clone-format 2 --image-feature layering,deep-flatten
|
||||
- Delete temporary snapshot created
|
||||
- Check the image chain depth, if the Softlimit is reached Add a task Flatten
|
||||
the cloned image and return success. If the depth is reached hardlimit Add a
|
||||
task Flatten the cloned image and return snapshot status ready as false
|
||||
|
||||
### RBD CLI commands to create snapshot
|
||||
|
||||
```bash
|
||||
[$] rbd snap ls <RBD image for src k8s volume> --all
|
||||
// If the parent has more snapshots than the configured `maxsnapshotsonimage`
|
||||
add backgound tasks to flatten the temporary cloned images( temporary cloned
|
||||
images name will be same as snapshot names)
|
||||
[$] ceph rbd task add flatten <RBD image for temporary snap images>
|
||||
[$] rbd snap create <RBD image for src k8s volume>@<random snap name>
|
||||
[$] rbd clone --rbd-default-clone-format 2 --image-feature
|
||||
layering,deep-flatten <RBD image for src k8s volume>@<random snap>
|
||||
<RBD image for temporary snap image>
|
||||
[$] rbd snap rm <RBD image for src k8s volume>@<random snap name>
|
||||
[$] rbd snap create <BD image for temporary snap image>@<random snap name>
|
||||
// check the depth,if the depth is greater than configured hardlimit add a
|
||||
// task to flatten the cloned image return snapshot status ready as false,
|
||||
// if the depth is greater than softlimit add a task to flatten the image
|
||||
// and return success
|
||||
[$] ceph rbd task add flatten <RBD image for temporary snap image>
|
||||
```
|
||||
|
||||
## Create PVC from a snapshot (datasource snapshot)
|
||||
|
||||
### steps to create a pvc from snapshot
|
||||
|
||||
- Check the depth(n) of the cloned image if n>=(hardlimit -2) Add task to
|
||||
flatten the image and return ABORT (to avoid image leak)
|
||||
- Clone a new image from the snapshot with user-provided options
|
||||
|
||||
### RBD CLI commands to create clone from snapshot
|
||||
|
||||
```bash
|
||||
// check the depth,if the depth is greater than configured (hardlimit)
|
||||
// Add a task to value flatten the cloned image
|
||||
[$] ceph rbd task add flatten <RBD image for temporary snap image>
|
||||
[$] rbd clone --rbd-default-clone-format 2 --image-feature <k8s dst vol config>
|
||||
<RBD image for temporary snap image>@<random snap name>
|
||||
<RBD image for k8s dst vol>
|
||||
// check the depth,if the depth is greater than configured hardlimit add a task
|
||||
// to flatten the cloned image return ABORT error, if the depth is greater than
|
||||
// softlimit add a task to flatten the image and return success
|
||||
[$] ceph rbd task add flatten <RBD image for k8s dst vol>
|
||||
```
|
||||
|
||||
## Delete a snapshot
|
||||
|
||||
### steps to delete a snapshot
|
||||
|
||||
- Delete temporary snapshot on temporary cloned image
|
||||
- Move the temporary cloned image to trash
|
||||
- Add task to remove the image from trash
|
||||
|
||||
### RBD CLI commands to delete a snapshot
|
||||
|
||||
```bash
|
||||
[$] rbd snap create <RBD image for temporary snap image>@<random snap name>
|
||||
[$] rbd trash mv <RBD image for temporary snap image>
|
||||
[$] ceph rbd task trash remove <RBD image for temporary snap image ID>
|
||||
```
|
||||
|
||||
## Delete a Volume (PVC)
|
||||
|
||||
With earlier implementation to delete the image we used to add a task to remove
|
||||
the image with new changes this cannot be done as the image may contains
|
||||
snapshots or linking.so we will be following below steps to delete an
|
||||
image(this will be applicable for both normal image and cloned image)
|
||||
|
||||
### steps to delete a volume
|
||||
|
||||
- Move the rbd image to trash
|
||||
- Add task to remove the image from trash
|
||||
|
||||
### RBD CLI commands to delete a volume
|
||||
|
||||
```bash
|
||||
1) rbd trash mv <image>
|
||||
2) ceph rbd task trash remove <image>
|
||||
```
|
||||
|
||||
## Volume cloning (datasource pvc)
|
||||
|
||||
Refer
|
||||
[volume-cloning](https://kubernetes.io/docs/concepts/storage/volume-pvc-datasource/)
|
||||
for more information realted to Volume cloning in kubernetes.
|
||||
|
||||
### steps to create a Volume from Volume
|
||||
|
||||
- Check the depth(n) of the cloned image if n>=((hard limit) -2) Add task to
|
||||
flatten the image and return about (to avoid image leak)
|
||||
- Create snapshot of rbd image
|
||||
- Clone the snapshot (temp clone)
|
||||
- Delete the snapshot
|
||||
- Snapshot the temp clone
|
||||
- Clone the snapshot (final clone)
|
||||
- Delete the snapshot
|
||||
|
||||
### RBD CLI commands to create a Volume from Volume
|
||||
|
||||
```bash
|
||||
// check the image depth of the parent image if flatten required add a
|
||||
// task to flatten image and return ABORT to avoid leak(same hardlimit and
|
||||
// softlimit check will be done)
|
||||
[$] ceph rbd task add flatten <RBD image for src k8s volume>
|
||||
[$] rbd snap create <RBD image for src k8s volume>@<random snap name>
|
||||
[$] rbd clone --rbd-default-clone-format 2 --image-feature
|
||||
layering,deep-flatten <RBD image for src k8s volume>@<random snap>
|
||||
<RBD image for temporary snap image>
|
||||
[$] rbd snap rm <RBD image for src k8s volume>@<random snap name>
|
||||
[$] rbd snap create <RBD image for temporary snap image>@<random snap name>
|
||||
[$] rbd clone --rbd-default-clone-format 2 --image-feature <k8s dst vol config>
|
||||
<RBD image for temporary snap image>@<random snap name>
|
||||
<RBD image for k8s dst vol>
|
||||
[$] rbd snap rm <RBD image for src k8s volume>@<random snap name>
|
||||
```
|
||||
Loading…
Reference in New Issue
Block a user