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>

ndctl                                              2024-04-08                            NDCTL-READ-INFOBLOCK(1)