cannot list rbd snapshots via rbd-target-api about ceph-iscsi HOT 3 OPEN

It's not currently exposed via the API. Right now, the gwcli just grabs it directly. There are several things that the gwcli does directly and eventually it would be great to eliminate it's usage of python-rados/python-rbd.

from ceph-iscsi.

Thanks for info. Hmm I would love to be able to contribute something perhaps I can try not sure if I have the coding chops to do so but for those things that the API cant do directly is it feasible for the internals of the API to either use the same method gwcli uses or for the API to rely on the gwcli to facilitate grabbing the information? I know the gwcli relies on the API itself so its kind of backwards to do that, perhaps?

from ceph-iscsi.

The API is already hooked into and using python-rados and python-rbd, so it should be relatively straightforward.

I think the hardest part would be the full disk scan [1] since right now it uses multiple threads to open and extract metadata from images. If you have a lot of RBD images in-use for backing LUNs, you wouldn't necessarily want the REST API call to block for 10s of seconds while it gathers the data, so you might need to have it pre-cached and periodically refreshed in the background of the API.

There is also a disk-specific data gatherer [2] which wouldn't be too hard to just implement as a REST call since opening a single image in read-only mode should be relatively fast. For this case, you could probably tweak the existing /disk/<pool>/<image> REST API [3] to return the backing image meta-data (features, size, and snapshots).

[1] https://github.com/ceph/ceph-iscsi/blob/master/gwcli/storage.py#L55
[2] https://github.com/ceph/ceph-iscsi/blob/master/gwcli/storage.py#L746
[3] https://github.com/ceph/ceph-iscsi/blob/master/rbd-target-api.py#L978

from ceph-iscsi.