NVME-ID-NS(1)

✨ NAME ✨

okay bestie, meet NVME-ID-NS(1) from the NVMe Manual — the page for nvme-show-regs. It reads and shows the defined NVMe controller registers for NVMe over PCIe or the controller properties for NVMe over Fabrics. No cap. 💖

🌸 SYNOPSIS 🌸

nvme [<global-options>] show-regs <device>

🦋 DESCRIPTION 🦋

So here's the vibe: it reads and shows the controller registers. For an NVMe over PCIe controller, nvme maps its PCI memory space through sysfs (the resource0 file of the PCI device) and reads them there. For an NVMe over Fabrics controller, it reads its properties with Property Get commands: CAP, VS, CC, CSTS and the ones of NSSR, NSSD and CRTO the controller implements.

The <device> parameter is mandatory and must be the nvme admin character device (ex: /dev/nvme0). Literally required, bestie.

With -v, the fields of each register are shown decoded. The JSON output has the value of each register under its name, with -v an object of the value and its decoded fields. The binary output is the registers from 0h to E1Bh, as they are in the PCI memory space, with zeros for the ones not read.

🎀 OPTIONS 🎀

🌈 GLOBAL OPTIONS 🌈

The following options are defined at the top-level nvme command and are available to this subcommand:

• --dry-run — Print the command that would be executed, but do not actually execute it.
• --no-ioctl-probing — Disable probing for 64-bit IOCTL support.
• --no-retries — Disable retry logic on transient errors.
• -o <fmt>, --output-format=<fmt> — Set the reporting format to normal, tabular, 'json, or binary. Only one output format may be used at a time.
• --output-format-version=<version> — Select the output format version. Version 1 uses the original field naming, while version 2 (default) provides more consistent and script-friendly field names. Other versions are rejected.
• --quiet — Suppress informational messages. Errors are still reported, and --quiet cancels any --verbose for the library log level.
• --set-options=<key=value>[,<key=value>...] — Set libnvme library options for this invocation. Supported keys are force-4k, mi-probe-enabled, test-base-dir and test-sysfs-dir.
• --timeout=<ms> — Set the timeout for the command in milliseconds. infinite or -1 waits without a time limit (0xffffffff).
• -v, --verbose — Increase the level of detail in the output. May be specified multiple times to further increase verbosity.

These options can also be set as machine-wide defaults in nvme-cli.conf(5). A command-line flag always overrides the file.

💅 EXAMPLES 💅

• Show the NVMe over PCIe controller registers or the NVMe over Fabric controller properties in a binary format:

# nvme show-regs /dev/nvme0 -o binary

• Show the NVMe over PCIe controller registers or the NVMe over Fabric controller properties in a human readable format:

# nvme show-regs /dev/nvme0 -v

• Show the NVMe over PCIe controller registers or NVMe-oF controller properties in a json format:

# nvme show-regs /dev/nvme0 -o json

👑 NVME 👑

Part of the nvme-user suite.

mwah 💋 — source/version NVMe · date 10/30/2026 · manual NVME-ID-NS(1) ✨🫶