This is different from multipath on say a multi-controller PCI device
and trying to expose both those controllers through passthru. this is
where the problems we are discussing come up.
I *think* there is some confusion. I *think* Sagi is talking about network multi-path (i.e. the ability for the host to connect to a controller on the target via two different network paths that fail-over as needed). I *think* Logan is talking about multi-port PCIe NVMe devices that allow namespaces to be accessed via more than one controller over PCIe (dual-port NVMe SSDs being the most obvious example of this today).
Yes, I was referring to fabrics multipathing which is somewhat
orthogonal to the backend pci multipathing (unless I'm missing
something).
But it's the multipath through different ports that
seems important for fabrics. ie. If I have a host with a path through
RDMA and a path through TCP they should both work and allow fail over.
Yes, or even two paths that are both RDMA or both TCP but which take a different path through the network from host to target.
Our real-world use case is to support our PCI device which has a bunch
of vendor unique commands and isn't likely to support multiple
controllers in the foreseeable future.
I think solving passthru for single-port PCIe controllers would be a good start.
Me too.
