nvme-get-feature(1)

===================

NAME

----

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

SYNOPSIS

--------

[verse]

'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]

			  [--human-readable | -H]

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.

-H::

--human-readable::

	This option will parse and format many of the bit fields

	into human-readable formats.

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

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Part of the nvme-user suite