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>] [--cdw11=<cdw11>]
                                 [--data-len=<data-len> | -l <data-len>]
                                 [--sel=<select> | -s <select>]
                                 [--raw-binary | -b]

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               │
           └────────┴────────────────────────┘

       -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

       --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.

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

       •   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                                               12/10/2017                                NVME-GET-FEATURE(1)