NVMFT(4)

📦 version 15.1, in freebsd 15.1, nixpkgs unstable

💅 NVMFT(4) — like, the whole kernel interfaces manual moment 🎀

okay so bestie, gather round, because this is nvmft from the Kernel Interfaces Manual and it is genuinely iconic. it's giving "server side of a whole storage situation" and i need you to be seated for this. ✨

🌸 NAME 🌸

nvmft — the NVM Express over Fabrics CAM Target Layer frontend. yes that's a lot of words. yes it slays. no cap. 💅

⭐ SYNOPSIS ⭐

so if you wanna compile this subsystem into the kernel (main character energy, no modules), you put these lines in your kernel configuration file:

device nvmft
device ctl

OR — and honestly this is the lowkey easier route — you can load the subsystem as a module at boot time by putting this line in loader.conf(5):

nvmft_load="YES"

both are valid. pick your fighter. 🫶

🦋 DESCRIPTION 🦋

so the nvmft driver provides the kernel component of an NVM Express over Fabrics controller. and if that phrase just made your brain go brrr, here's the vibe check: the NVMeoF controller is the server — it's the one exporting namespaces backed by local files and volumes out to remote hosts. it's literally giving hostess with the mostest. 💖

nvmft follows the dynamic controller model, which means it creates a new dynamic controller for each association. every friend group gets its own controller. periodt.

nvmft is implemented as a ctl(4) frontend, and it exports CAM Target Layer LUNs as namespaces to remote hosts. those LUNs can be configured via ctladm(8). 🎀

now, the associations between the local controller and remote hosts are managed using both the nvmfd(8) daemon and the ctladm(8) utility — it's a whole collab, not a solo era:

  • the nvmfd(8) daemon listens for new associations and handles the transport-specific negotiation before handing off connected queue pairs to nvmft, which then associates those queue pairs with a suitable controller instance. it's like a matchmaker but for queue pairs. 🧚
  • the nvlist ctladm(8) command lists active controllers — your little roster of who's currently online.
  • the nvterminate command terminates one or more associations between a local controller and a remote host. respectfully, it's the unfollow button. 💀
heads up bestie: associations require a supported transport — like nvmf_tcp(4) for associations using TCP/IP. no transport, no association. that's the rule. 🙈

🌈 SEE ALSO 🌈

go read them, they're all besties. 👑

🔥 HISTORY 🔥

the nvmft module first appeared in FreeBSD 15.0. a legend was born. ⭐

👑 AUTHORS 👑

the nvmft subsystem was developed by John Baldwin <jhb@FreeBSD.org> under sponsorship from Chelsio Communications, Inc. we love a sponsored icon. 🫶

and that's the whole page, bestie — no notes, ate and left no crumbs. 💜

sign-off: this Debian edition of the page is dated May 2, 2024, so go forth and export those namespaces responsibly ✨🎀💖

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