Commit Graph

11 Commits

Author SHA1 Message Date
Madhu Rajanna
07a916b84d rbd: mark image ready when image state is up+unknown
To recover from split brain (up+error) state the image need to be
demoted and requested for resync on site-a and then the image on site-b
should gets demoted.The volume should be marked to ready=true when the
image state on both the clusters are up+unknown because during the last
snapshot syncing the data gets copied first and then image state on the
site-a changes to up+unknown.

If the image state on both the sites are up+unknown consider that
complete data is synced as the last snapshot
gets exchanged between the clusters.

* create 10 GB of file and validate the data after resync

* Do Failover when the site-a goes down
* Force promote the image and write data in GiB
* Once the site-a comes back, Demote the image and issue resync
* Demote the image on site-b
* The status will get reflected on the other site when the last
  snapshot sync happens
* The image will go to up+unknown state. and complete data will
  be copied to site a
* Promote the image on site-a and use it

```bash
csi-vol-5633715e-a7eb-11eb-bebb-0242ac110006:
  global_id:   e7f9ec55-06ab-46cb-a1ae-784be75ed96d
  state:       up+unknown
  description: remote image demoted
  service:     a on minicluster1
  last_update: 2021-04-28 07:11:56
  peer_sites:
    name: e47e29f4-96e8-44ed-b6c6-edf15c5a91d6-rook-ceph
    state: up+unknown
    description: remote image demoted
    last_update: 2021-04-28 07:11:41
 ```

* Do Failover when the site-a goes down
* Force promote the image on site-b and write data in GiB
* Demote the image on site-b
* Once the site-a comes back, Demote the image on site-a
* The images on the both site will go to split brain state

```bash
csi-vol-37effcb5-a7f1-11eb-bebb-0242ac110006:
  global_id:   115c3df9-3d4f-4c04-93a7-531b82155ddf
  state:       up+error
  description: split-brain
  service:     a on minicluster2
  last_update: 2021-04-28 07:25:41
  peer_sites:
    name: abbda0f0-0117-4425-8cb2-deb4c853da47-rook-ceph
    state: up+error
    description: split-brain
    last_update: 2021-04-28 07:25:26
```
* Issue resync
* The images cannot be resynced because when we issue resync
  on site a the image on site-b was in demoted state
* To recover from this state (promote and then demote the
  image on site-b after sometime)

```bash
csi-vol-37effcb5-a7f1-11eb-bebb-0242ac110006:
  global_id:   115c3df9-3d4f-4c04-93a7-531b82155ddf
  state:       up+unknown
  description: remote image demoted
  service:     a on minicluster1
  last_update: 2021-04-28 07:32:56
  peer_sites:
    name: e47e29f4-96e8-44ed-b6c6-edf15c5a91d6-rook-ceph
    state: up+unknown
    description: remote image demoted
    last_update: 2021-04-28 07:32:41
```
* Once the data is copied we can see that  the image state
  is moved to up+unknown on both sites
* Promote the image on site-a and use it

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-05-05 13:38:29 +00:00
Madhu Rajanna
cfc88c9910 rbd: discard up+unknown state in ResyncVolume
incase if the image is promoted and demoted the
image state will be set to up+unknown if the image
on the remote cluster is still in demoted state.

when user changes the state from primary to secondary
and still the image is in demoted (secondary) state
in the remote cluster. the image state on both the cluster
will be on unknown state.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-15 17:13:06 +05:30
Madhu Rajanna
d7838defcf rbd: return FailedPrecondition error message
In case of the DR the image on the primary site cannot be
demoted as the cluster is down, during failover the image need
to be force promoted. RBD returns `Device or resource busy`
error message if the image cannot be promoted for above reason.
Return FailedPrecondition so that replication operator can send
request to force promote the image.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-06 14:12:41 +00:00
Madhu Rajanna
403532c9a6 rbd: use force from PromoteVolume Request
instead of fetching the force option from the
parameters. Use the Force field available in
the PromoteVolume Request.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-06 14:12:41 +00:00
Madhu Rajanna
385a751b8e rebase: rename kube-storage to csi-addons
as the org github.com/kube-storage is renamed
to github.com/csi-addons as the name kube-storage
was more generic.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-06 10:59:58 +00:00
Madhu Rajanna
448be70682 rbd: early check for disabled,disabling in DisableVolumeReplication
added early check for disabling and disabled
image mirroring state in DisableVolumeReplication

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-05 08:53:40 +00:00
Madhu Rajanna
fb3f7fe202 rbd: remove todo for image not found
Incase of resync the image will get deleted, gets
recreated and its a a time consuming operation.
It makes sense to return aborted error instead
of not found as we have omap data only the image
is missing in rbd pool.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-05 08:53:40 +00:00
Madhu Rajanna
95387c3b5e rbd: check for peer site status
Do resync if the image is in unknow or in error
state.

Check for the current image state for up+stopped
or up+replaying and also all peer site status
should be un up+stopped to confirm that resyncing
is done and image can be promoted and used.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-05 08:53:40 +00:00
Madhu Rajanna
c822ad460d rbd: add a check for image mirror disabling state
the rbd mirror state can be in enabled,disabled
or disabling state. If the mirroring is not disabled
yet and still in disabling state. we need to
check for it and return abort error message if
the mirroring is still getting disabled.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-05 08:53:40 +00:00
Madhu Rajanna
aaf6b571b8 rbd: Add ReplicationServer struct for replication operations
added ReplicationServer struct for the replication related
operation it also embed the ControllerServer which
already implements the helper functions like locking/unlocking etc.

removed getVolumeFromID and cleanup functions for better
code readability and easy maintaince.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-04-05 08:53:40 +00:00
Madhu Rajanna
6e941539b5 rbd: implement volume replication spec
implemented the volume replication spec
for the rbd mirroring.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>
2021-03-16 13:06:44 +00:00