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From reading the article, it sounds like NVMe-oF exposes a drive directly to a network, but I don’t really get how that works. Does the drive still get connected to a host? How does this compare to other technologies for having networked storage, like NFS?

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It still needs to be connected to a host. This is an alternative to iSCSI. Instead of using the SCSI protocol, it uses the NVMe protocol.

And the use case is when you have a sufficiently high-performance storage controller that the SCSI protocol (that you are tunneling over IP or Fibre channel) becomes a bottle neck.

SCSI still does have some tricks (eg VAAI) which I don't think have NVMe counterparts yet?

Still, even just being able to get rid of the huge complexity and historical baggage of SCSI is a good thing. One of my favourite examples is how the spec defines the LUN number to not be a number.

I think NVMe is pretty close to feature parity with SCSI, or at least the subset of SCSI that is actually relevant. NVMe includes thin provisioning, some copy offload, atomic operations and of course deallocate/trim—which I think covers all the VAAI features.

> it sounds like NVMe-oF exposes a drive directly to a network

The drive is connected to a storage device. Storage is exposed by the device to network. Exposed storage and the drive do not correspond 1to1 (redundancy, etc.)

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