I have no experience about what you are trying to achieve, but rdma and related technologies (infiniband, qlogic, sr-iov, ROCE) is not it. These are network technologies that permit high bandwidth/low latency data transfer between hosts. Most of these bypass the IP stack entirely.

Infiniband is a network stack that enable RDMA, it’s only vendor is now NVIDIA which acquired mellanox. Qlogic was another vendor, but it got acquired by Intel that tried to market it as Omnipath, but it was spinned off to Cornelis network.

Sr-iov is a way to share an infiniband card to a virtual machine on the same host.

ROCE is an implementation of the rdma software stack over ethernet instead of infiniband.

The target storage device for the image can be over the network if that’s an option for you.

I admit the downvote is weird.