NAME

       ndctl-read-infoblock - read and optionally parse the info-block a namespace

SYNOPSIS

       ndctl read-infoblock <namespace0.0> [<namespace1.0>..<namespaceN.Y>] [<options>]

DESCRIPTION

       As described in the theory of operation section of ndctl-create-namespace(1), the raw
       capacity of a namespace may encapsulate a personality, or mode of operation. Specifically,
       the mode may be set to one of "sector", "fsdax", and "devdax". Each of those modes is
       defined by an info-block format that uniquely identifies the mode of operation. The
       read-infoblock command knows the location (relative to the start of the namespace) and
       field definition of those data structures.

       Note that unlike a partition table info-block is not exposed by default, so the namespace
       needs to be disabled before the info-block can be accessed.

EXAMPLE

       ndctl disable-namespace namespace0.0
       disabled 1 namespace
       ndctl read-infoblock -j namespace0.0
       [
         {
           "dev":"namespace0.0",
           "signature":"NVDIMM_PFN_INFO",
           "uuid":"56b11990-66b1-4d91-9cac-ca084c051259",
           "parent_uuid":"00000000-0000-0000-0000-000000000000",
           "flags":0,
           "version":"1.3",
           "dataoff":69206016,
           "npfns":1031680,
           "mode":2,
           "start_pad":0,
           "end_trunc":0,
           "align":2097152
         }
       ]

OPTIONS

       <namespace(s)>
           One or more namespaceX.Y device names. The keyword all can be specified to operate on
           every namespace in the system, optionally filtered by bus id (see --bus= option), or
           region id (see --region= option).

       -V, --verify
           Attempt to validate that the info-block is self consistent by validating the embedded
           checksum, and that info-block formats that contain a parent-uuid attribute also match
           the base-uuid of the namespace.

       -o, --output
           Output file

       -j, --json
           Parse the info-block data into json.

       -u, --human
           Enable json output and convert number formats to human readable strings, for example
           show the size in terms of "KB", "MB", "GB", etc instead of a signed 64-bit numbers per
           the JSON interchange format (implies --json).

       -r, --region=
           A regionX device name, or a region id number. Restrict the operation to the specified
           region(s). The keyword all can be specified to indicate the lack of any restriction,
           however this is the same as not supplying a --region option at all.

COPYRIGHT

       Copyright © 2016 - 2022, Intel Corporation. License GPLv2: GNU GPL version 2
       http://gnu.org/licenses/gpl.html. This is free software: you are free to change and
       redistribute it. There is NO WARRANTY, to the extent permitted by law.

SEE ALSO

       ndctl-create-namespace(1), UEFI NVDIMM Label Protocol
       <http://www.uefi.org/sites/default/files/resources/UEFI_Spec_2_7.pdf>