> For the complete documentation index, see [llms.txt](https://docs.pmem.io/ndctl-user-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pmem.io/ndctl-user-guide/v71.1/concepts/regions.md).

# Regions

A generic REGION device is registered for each PMEM range or BLK-aperture set. Regions represent the physical persistent memory devices in an interleaved or non-interleaved set. LIBNVDIMM provides a built-in driver for these REGION devices. This driver is responsible for reconciling the aliased DPA mappings across all regions, parsing the LABEL, if present, and then emitting NAMESPACE devices with the resolved/exclusive DPA-boundaries for the `nd_pmem` or `nd_blk` device driver to consume.

Refer to [Managing Regions](/ndctl-user-guide/v71.1/managing-regions.md) for more information.


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