nvme-id-ctrl

NVME-ID-CTRL(1) NVMe Manual NVME-ID-CTRL(1)

NAME

   nvme-id-ctrl - Send NVMe Identify Controller, return result and structure

SYNOPSIS

   nvme id-ctrl <device> [--vendor-specific | -V] [--raw-binary | -b]
                           [--output-format=<fmt> | -o <fmt>] [--verbose | -v]

DESCRIPTION

   For the NVMe device given, sends an identify controller command and provides the result and returned structure.

   The <device> parameter is mandatory and may be either the NVMe character device (ex: /dev/nvme0), or a namespace block device (ex: /dev/nvme0n1).

   On success, the structure may be returned in one of several ways depending on the option flags; the structure may be parsed by the program or the raw buffer may be printed to stdout.

OPTIONS

   -b, --raw-binary
       Print the raw buffer to stdout. Structure is not parsed by program. This overrides the vendor specific and human readable options.

   -V, --vendor-specific
       In addition to parsing known fields, this option will dump the vendor specific region of the structure in hex with ascii interpretation.

   -H, --human-readable
       This option will parse and format many of the bit fields into human-readable formats.

   -o <fmt>, --output-format=<fmt>
       Set the reporting format to normal, json or binary. Only one output format can be used at a time.

   -v, --verbose
       Increase the information detail in the output.

EXAMPLES

   •   Has the program interpret the returned buffer and display the known fields in a human readable format:

           # nvme id-ctrl /dev/nvme0

   •   In addition to showing the known fields, has the program to display the vendor unique field:

           # nvme id-ctrl /dev/nvme0 --vendor-specific
           # nvme id-ctrl /dev/nvme0 -V

       The above will dump the vs buffer in hex since it doesn’t know how to interpret it.

   •   Have the program return the raw structure in binary:

           # nvme id-ctrl /dev/nvme0 --raw-binary > id_ctrl.raw
           # nvme id-ctrl /dev/nvme0 -b > id_ctrl.raw

       It is probably a bad idea to not redirect stdout when using this mode.

   •   Alternatively you may want to send the data to another program that can parse the raw buffer.

           # nvme id-ctrl /dev/nvme0 --raw-binary | nvme_parse_id_ctrl

       The parse program in the above example can be a program that shows the structure in a way you like. The following program is such an example that will parse it and can accept the
       output through a pipe, '|', as shown in the above example, or you can 'cat' a saved output buffer to it.

       /* File: nvme_parse_id_ctrl.c */

       #include <linux/nvme.h>
       #include <stdio.h>
       #include <unistd.h>

       int main(int argc, char **argv)
       {
               unsigned char buf[sizeof(struct nvme_id_ctrl)];
               struct nvme_id_ctrl *ctrl = (struct nvme_id_ctrl *)buf;

               if (read(STDIN_FILENO, buf, sizeof(buf)))
                       return 1;

               printf("vid   : %#x\n", ctrl->vid);
               printf("ssvid : %#x\n", ctrl->ssvid);
               return 0;
       }

NVME

   Part of the nvme-user suite

NVMe 05/02/2025 NVME-ID-CTRL(1)