NVME_TCP Discovery Client Connection Method

The NVMe-over-Fabrics specification defines the concept of a discovery controller that an NVMe host can query on a fabric network to discover NVMe subsystems. These subsystems are contained in NVMe targets that can be connected from the network.

The discovery-client is a deployable service running under systemd. Every five seconds (configurable), it will poll the discoveryservices in the cluster.

The discovery-client command requires several parameters that you can query for the NVMe/TCP storage server to be discovered and connected to. Note that the base NVMe specification defines the NQN (NVMe Qualified Name) format, which an NVMe endpoint (device, subsystem, etc) must follow to guarantee a unique name under the NVMe standard. In particular, the host NQN uniquely identifies the NVMe host, and can be used by the discovery controller to control what NVMe target resources are allocated to the NVMe host for a connection.