Hi Holger,

Looking at the cinder support matrix[1], only Pure storage has declared support for RoCE (I think they mean ROCEv2 only as RoCEv1 is rarely used) and os-brick does support RoCEv2.
It should technically "work" with Infiniband hardware, as the main protocol is RDMA either over infiniband or ethernet cards but I have no experience trying it so better to ask the vendor i.e. Pure about it.
Probably @Simon Dodsley can provide more information on it.

[1] https://docs.openstack.org/cinder/latest/reference/support-matrix.html

Thanks
Rajat Dhasmana

On Mon, Feb 17, 2025 at 7:09 PM Sean Mooney <smooney@redhat.com> wrote:

On 17/02/2025 12:58, holger.bielefeld@uponu.com wrote:
> Hi all,
>
> does anyone know if NVMe over RDMA is supported to attach it with Cinder/Nova to a QemuKVM Hypervisor?

technically yes.

it depend on if you cinder driver supports nvme over rdma as well.

ceph obviously does not as it use RBD to export the block storage.

the mounting of the NVMEoF devicve is handled by os-brick so form a
nova/qemu point of view its a host mounted block device. as such there
is no difference between that and iscsi because qemu is not directly
connecting to the storage backend.


> In addition to our ceph, we would also like to connect a block storage and in order to be able to retrieve the full performance, this must be done with the above-mentioned connection.
>
> Thanks in advance.
>
> Holger
>