NDCTL-READ-LABELS(1)

📦
version 85 · 15 versions
, in fedora 43, fedora 44, ubuntu stonking

✨ NDCTL-READ-LABELS ✨

okay bestie, welcome to the ndctl manual, this one's NDCTL-READ-LABELS(1) and it's giving "let me peek inside your DIMM's label area" energy 💅

🌸 NAME 🌸

ndctl-read-labels — read out the label area on a dimm or set of dimms

🎀 SYNOPSIS 🎀

ndctl read-labels <nmem0> [<nmem1>..<nmemN>] [<options>]

🦋 DESCRIPTION 🦋

so like, the namespace label area? it's a small persistent partition of capacity that lives on some NVDIMM devices, no cap. and what's it for? it's literally the thing that provisions one, or more, namespaces out of regions. main character behavior tbh 👑

this command dumps the raw binary data in a dimm's label area — either straight to stdout or out to a file, your call. and in the multi-dimm case? the data gets concatenated. fr fr, all mushed together. 🌈

💖 OPTIONS 💖

  • <memory device(s)> — a nmemX device name, or a dimm id number. this restricts the operation to the dimm(s) you picked. you can pass the keyword all to say "no restriction bestie" — but lowkey that's the same as just not supplying a --dimm option at all, so do with that what you will 🙈
  • -s, --size= — limits the operation to the given number of bytes. a size of 0 means operate over the entire label capacity. zero = all of it, iconic. ✨
  • -O, --offset= — begins the operation at the given offset into the label area. gotta know where to start, yk? 🎯
  • -b, --bus= — a bus id number, or a provider string (e.g. "ACPI.NFIT"). restricts the operation to the specified bus(es). the keyword all can be specified to indicate the lack of any restriction, however this is the same as not supplying a --bus option at all. same deal as before, we love consistency 🫶
  • -v — turns on verbose debug messages in the library (if ndctl was built with logging and debug enabled). yes, if. conditional slay 💅
  • -I, --index — limits the span of the label operation to just the index-block area. super useful for figuring out whether the dimm label area is initialized or not. 👀
⚠️ note that this option and --size/--offset are mutually exclusive. pick a lane bestie, you cannot have both 😭
  • -o, --output — output file
  • -j, --json — parses the label data into json, assuming the NVDIMM Namespace Specification format. structured data era 💀
  • -u, --human — enables json output and converts number formats into human readable strings — like showing the size in terms of "KB", "MB", "GB", etc instead of signed 64-bit numbers per the JSON interchange format. (this implies --json). your eyeballs will thank you 🍓

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 🌟

okay that's the whole page, you ate that 🧚 this was ndctl manual, version ndctl, dated 2026-07-07 — mwah, go read some labels bestie, periodt 💜

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