nvme-get-feature

NVME-GET-FEATURE(1) NVMe Manual NVME-GET-FEATURE(1)

NAME

   nvme-get-feature - Gets an NVMe feature, returns applicable results

SYNOPSIS

   nvme get-feature <device> [--namespace-id=<nsid> | -n <nsid>]
                           [--feature-id=<fid> | -f <fid>]
                           [--uuid-index=<uuid-index> | -U <uuid_index>]
                           [--data-len=<data-len> | -l <data-len>]
                           [--sel=<select> | -s <select>]
                           [--raw-binary | -b] [--cdw11=<cdw11> | -c <cdw11>]
                           [--human-readable | -H] [--changed | -C]
                           [--output-format=<fmt> | -o <fmt>] [--verbose | -v]
                           [--timeout=<timeout> | -t <timeout>]

DESCRIPTION

   Submits an NVMe Get Feature admin command and returns the applicable results. This may be the feature’s value, or may also include a feature structure if the feature requires it (ex:
   LBA Range Type).

   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 returned feature’s structure (if applicable) may be returned in one of several ways depending on the option flags; the structure may parsed by the program and printed
   in a readable format if it is a known structure, displayed in hex, or the raw buffer may be printed to stdout for another program to parse.

OPTIONS

   -n <nsid>, --namespace-id=<nsid>
       Retrieve the feature for the given nsid. This is optional and most features do not use this value.

   -f <fid>, --feature-id=<fid>
       The feature id to send with the command. Value provided should be in hex.

   -s <select>, --sel=<select>
       Select (SEL): This field specifies which value of the attributes to return in the provided data:
       ┌────────┬────────────────────────┐
       │ Select │ Description            │
       ├────────┼────────────────────────┤
       │ 0      │ Current                │
       ├────────┼────────────────────────┤
       │ 1      │ Default                │
       ├────────┼────────────────────────┤
       │ 2      │ Saved                  │
       ├────────┼────────────────────────┤
       │ 3      │ Supported capabilities │
       ├────────┼────────────────────────┤
       │ 4-7    │ Reserved               │
       └────────┴────────────────────────┘

   -U <uuid-index>, --uuid-index=<uuid-index>
       UUID Index of the feature

   -l <data-len>, --data-len=<data-len>
       The data length for the buffer returned for this feature. Most known features do not use this value. The exception is LBA Range Type

   -c <cdw11>, --cdw11=<cdw11>
       The value for command dword 11, if applicable.

   -b, --raw-binary
       Print the raw feature buffer to stdout if the feature returns a structure.

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

   -C, --changed
       This option will show feature changed.

   -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.

   -t <timeout>, --timeout=<timeout>
       Override default timeout value. In milliseconds.

EXAMPLES

   •   Retrieves the feature for Number of Queues, or feature id 7:

           # nvme get-feature /dev/nvme0 -f 7

   •   The following retrieves the feature for the LBA Range Type, which implicitly requires a buffer and will be printed to the screen in human readable format:

           # nvme get-feature /dev/nvme0 -f 3

   •   Retrieves the feature for the some vendor specific feature and specifically requesting a buffer be allocate for this feature, which will be displayed to the user in as a hex dump:

           # nvme get-feature /dev/nvme0 -f 0xc0 -l 512

       Get feature with UUID index

       # nvme get-feature /dev/nvme0 -f 0xc0 -l 512 -U 0x1

   •   The following retrieves the feature for the LBA Range Type, which implicitly requires a buffer and will be saved to a file in its raw format:

           # nvme get-feature /dev/nvme0 -f 3 --raw-binary > lba_range.raw

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

NVME

   Part of the nvme-user suite

NVMe 05/02/2025 NVME-GET-FEATURE(1)