NVME-SET-REG(1)                   NVMe Manual                  NVME-SET-REG(1)

NAME
       nvme-set-reg - Writes and shows the defined NVMe controller register

SYNOPSIS
       nvme [<global-options>] set-reg <device>
                               [--register=<name> | -r <name>] [--offset=<offset> | -O <offset>]
                               [--value=<val> | -V <val>] [--mmio32 | -m]

DESCRIPTION
       Writes a controller register: of an NVMe over PCIe controller in its
       PCI memory space, of an NVMe over Fabrics controller, which has no PCI
       memory space, the property with a Property Set command.

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

OPTIONS
       -r <name>, --register=<name>
           The register to write, by name: one of the registers the host may
           write, intms, intmc, cc, csts, nssr, aqa, asq, acq, bprsel, bpmbl,
           cmbmsc, nssd, pmrctl, pmrmscl, pmrmscu.

       -O <offset>, --offset=<offset>
           The register to write, by offset or name, e.g. 0x14 or cc.

       -V <val>, --value=<val>
           The value to write. A 32 bit register refuses a larger value.

       -m, --mmio32
           Write a 64 bit register as two 32 bit accesses.

       The options --cc=<val>, --aqa=<val> and so on of earlier versions, one
       for each register the host may write, still work, but are deprecated:
       use --register and --value.

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
       o   Write 0x460000 to the Controller Configuration register

               # nvme set-reg /dev/nvme0 --register=cc --value=0x460000

NVME
       Part of the nvme-user suite.

NVMe                              10/30/2026                   NVME-SET-REG(1)