Executing "ndctl disable-dimm nmem0" returns "nmem0 is active, skipping.."

Applies To

  • Linux
  • ndctl utility
  • Systems with Persistent Memory

Issue

When disabling an persistent memory device (nmem), a notice is displayed indicating it is active, eg:

# ndctl disable-dimm nmem0
nmem0 is active, skipping...
disabled 0 nmem

Cause

The message indicates there’s at least one active/enabled Region and/or Namespace using the NVDIMM.

Solution

All active/enabled Regions and Namespaces must be destroyed an/or disabled prior to disabling the dimm.

  1. List the current configuration (Namespaces, Regions, DIMMs):
# ndctl list -NRD
  1. Verify no fsdax or devdax namespaces are mounted or in-use by running applications:
// Check for mounted file systems using the pmem devices
# df -h

// Check for any running processes that are currently accessing the namespaces
# fuser /dev/pmem0
  1. Destroy or disable the namespace(s)
# ndctl destroy-namespace namespace0.0
  1. Disable the regions used by the persistent memory decvice(s) that needs to be disabled:
# ndctl disable-region region0
  1. Disable the persistent memory device (nmem)
# ndctl disable-dimm nmem0
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    Copyright© kb.pmem.io 2020. All rights reserved.
  • Document ID

    100000017
  • Creation Date

    2020-03-12

Copyright© kb.pmem.io 2020. All rights reserved.