Re: [Libguestfs] [PATCH v7 6/6] v2v: Add -o rhv-upload output mode (RHBZ#1557273).

> > > + sparse = params['output_sparse'], > > > > > The user cannot configure that. This must be based on the image > > format. The current coded may create images in unsupported > > combinations, e.g. raw/sparse on block storage, or fail validation > > in engine. > > In virt-v2v this can be configured using ‘-oa’. What are the possible > combinations? > I could not find documentation for this in the ovirt engine sdk. There is http://ovirt.github.io/ovirt-engine-sdk/master/ but it is not very useful for anything. The ovirt-engine REST API has real documentation here: http://ovirt.github.io/ovirt-engine-api-model/master But I could not find any documentation about creating disks there, so the above is based on current system behavior. When creating disks from the UI, the user select the storage domain (implicitly selecting the file/block), and the allocation policy (thin/preallocated). The user cannot select the image format when creating disk, ovirt will choose the image format and sparse for you. storage type allocation | image format sparse creating ---------------------------|----------------------------------------------------------------- file thin | raw true sparse file of provisioned_size bytes file preallocated | raw false preallocated file of provisioned_size bytes block thin | qcow2 true logical volume of initial_size bytes block preallocated | raw false logical volume of provisioned_size bytes When uploading disk, the user select a file, implicitly selecting the image format (raw/qcow2), and the storage domain, implicitly selecting the storage type (file/block). oVirt selects the allocation and sparse value for you. storage type image format | allocation sparse creating ---------------------------|--------------------------------------------------------------- file qcow2 | thin true sparse file of image size bytes file raw | thin true sparse file of provisioned_size bytes block qcow2 | thin true logical volume of initial_size bytes block raw | preallocated false logical volume of provisioned_size bytes Notes: - file,qcow2 cannot be created from the UI. - no way to create preallocated uploading from the UI (looks like a bug to me) When using the sdk, you can select both the image format and sparse, so you can create invalid combinations. oVirt selects the allocation for you. storage type image format sparse | allocation creating -----------------------------------|-------------------------------------------------------- file qcow2 true | thin sparse file of image size bytes file raw false | preallocated preallocated file of provisioned_size bytes file raw true | thin sparse file of provisioned_size bytes file qcow2 false | - unsupported block qcow2 true | thin logical volume of initial_size bytes block raw false | preallocated logical volume of provisioned_size bytes block qcow2 false | - unsupported block raw true | - unsupported The only case when selecting the sparse value is useful is raw file on file based storage domain, allowing creation of sparse or preallocated disk.

I guess you can check if a storage domain is file based or block basedu using the SDK, but I'm not familiar with it.

Daniel, do we expose this info? > [snipped] > > > > > +# Can we issue zero, trim or flush requests? > > > > > +def get_options(h): > > > + if h['got_options']: > > > + return > > > + h['got_options'] = True > > > + > > > + http = h['http'] > > > + transfer=h['transfer'] > > > + > > > + http.putrequest("OPTIONS", h['path']) > > > + http.putheader("Authorization", transfer.signed_ticket) > > > + http.endheaders() > > > + > > > + r = http.getresponse() > > > + if r.status == 200: > > > + j = json.loads(r.read()) > > + h['can_zero'] = "zero" in j['features'] > > > + h['can_trim'] = "trim" in j['features'] > > > + h['can_flush'] = "flush" in j['features'] > > > + > > > + # If can_zero is true then it means we're using the new > imageio > > > + # which never needs the Authorization header. > > > + if h['can_zero']: > > > + h['needs_auth'] = False > In older proxy, we do support OPTIONS, used for allowing access from enigne UI, but it does not return any content. Fortunately, we return httplib.NO_CONTENT so it is easy to detect. So we need to handle gracefully r.status = 204

> > > > > > > If we got here, we are working with new daemon or proxy, and both > > of them do not need auth, so we can set 'needs_auth' to False > > if OPTIONS returned 200 OK. > > Which is what this code does, unless I'm misunderstanding things. > Accessing readonly ticket will return empty features list, and h['needs_auth'] will be True, while this server does not need auth. Yes, it cannot happen with this code but it is not the right check.