nvme-subsystem-nqn · shipping · also Subsystem NVMe Qualified Name, SUBNQN

NVMe subsystem NQN

An NVMe subsystem NQN is the NVMe Qualified Name identifying an NVM subsystem, distinct from a host NQN and from individual namespace identifiers.

The subsystem NQN is reported in Identify Controller and is intended to remain permanent for the subsystem lifetime [1]. libnvme models the subsystem NQN separately from the transport address, transport service and host NQN [2].

Linux v6.12 normally uses the reported SUBNQN but can construct a compatibility value when it is missing, invalid or ignored by a device quirk [4]. A namespace identity must still be checked within the discovered subsystem before interpreting multipath state [5]. The well-known discovery NQN is not a unique identity for an ordinary storage subsystem [3].

Relations

related

nvm-subsystem, nvme-nsid, nvme-namespace-identifiers, nvme-host-identifier, multipath-nvme, nvme

Advantages

• Separates subsystem identity from the address of an individual transport endpoint.

Limitations

• One subsystem may expose multiple namespaces, so a matching NQN alone does not identify a particular volume.
• An NQN is a name, not a secret credential or proof that the target is authentic.

Citations

1. NVM Express Base Specification 2.0c, sections 4.5 and 4.5.1; copyright 2008-2022 NVM Express, Inc., all rights reserved (accessed 2026-10-16)
2. libnvme API: fabrics connection parameters and host identification (accessed 2026-10-16)
3. libnvme upstream types: nvmf_disc_log_entry.subnqn (accessed 2026-10-16)
4. Linux v6.12 NVMe host core: nvme_init_subnqn and subsystem discovery (accessed 2026-10-16)
5. NVMe multipath: ANA access states and Linux path policies (accessed 2026-10-16)

JSON: /data/terms/nvme-subsystem-nqn.json