nvme-get-property - Reads and shows the defined NVMe controller
property for NVMe over Fabric
nvme [<global-options>] get-property <device>
[--offset=<offset> | -O <offset>]
Reads and shows the defined NVMe controller property for NVMe over
Fabric.
-O <offset>, --offset=<offset>
The offset of the property, or the name of a register,
e.g. 0x14 or cc. The properties of a fabrics controller are cap (0x0), vs
(0x8), cc (0x14), csts (0x1c), nssr (0x20), nssd (0x64) and crto (0x68), the
transport may define more.
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.
•The following will run the get-property command
with offset 0
# nvme get-property /dev/nvme0 --offset=0x0 --verbose
Currently the CAP value is truncated to 32 bits due to a
limitation in the ioctl interface.
In a recent enough kernel, the 64 bit value is shown in kernel
traces.
•First enable traces by this command
# echo 1 > /sys/kernel/debug/tracing/events/nvme/enable
•Then look for NVMe Fabrics command (0x7f) at
trace
/sys/kernel/debug/tracing/trace
Part of the nvme-user suite