PowerFlex: How to Replace an NVDIMM in 15G PowerEdge Node

Summary: How to replace an NVDIMM in a PowerEdge server or PowerFlex Appliance.

This article applies to This article does not apply to This article is not tied to any specific product. Not all product versions are identified in this article.

Instructions

Before you begin:

  1. Save the output of the following commands in a notepad:
  • From the Control MDM:
scli --query_sds --sds_id <SDS ID>
  • From the SDS:
dmidecode --type memory | grep "Non-" -B 3 -A 3 | grep -E 'Locator|Serial' | grep -v Bank 

ndctl list -D 

ndctl list -N 

ndctl list -R


Procedure

  1. Remove all the storage devices from the SDS and wait for the Rebalance to finish.
  2. Once all the devices are removed from the cluster, remove all the acceleration devices.
  3. Once the server is no longer contributing any storage, power off the server and let the CE replace the NVDIMM. Before moving to step #4, make sure to complete steps #1-3.

    Before sanitizing NVDIMMs - REMOVE ALL SDS DEVICES!

  4. Power on the server and Boot into the BIOS. Select BIOS Settings > Memory Settings > Select Enabled for Sanitize All NVDIMMs.
  5. Save the changes and exit, then boot the server.
  6. Run the commands:
ndctl create-namespace --region=region0 --type=pmem --mode=devdax --align=4k --force
ndctl create-namespace --region=region1 --type=pmem --mode=devdax --align=4k --force 

Each DAX device name is displayed in the output as a chardev value. In the example output, DAX device names are dax0.0 and dax1.0. The full acceleration device names are /dev/dax0.0 and /dev/dax1.0. 

Example:

ndctl create-namespace --region=region0 --type=pmem --mode=devdax --align=4k --force
{
 "dev":"namespace0.0",
 "mode":"devdax",
 "map":"dev",
 "size":"31.50 GiB (33.82 GB)",
 "uuid":"44490109-0bff-4ca2-b68a-ae7a6b30a55f",
 "daxregion":{
 "id":1,
 "size":"31.50 GiB (33.82 GB)",
 "align":4096,
 "devices":[
 {
 "chardev":"dax0.0",
 "size":"31.50 GiB (33.82 GB)"
 }
 ]
 },
 "align":4096
}

 

ndctl create-namespace --region=region1 --type=pmem --mode=devdax --align=4k --force
{
 "dev":"namespace1.0",
 "mode":"devdax",
 "map":"dev",
 "size":"31.50 GiB (33.82 GB)",
 "uuid":"d48959c9-4b8c-4736-ad00-23afc0113fcd",
 "daxregion":{
 "id":1,
 "size":"31.50 GiB (33.82 GB)",
 "align":4096,
 "devices":[
 {
 "chardev":"dax1.0",
 "size":"31.50 GiB (33.82 GB)"
 }
 ]
 },
 "align":4096
}

 

NOTE: Two NVDIMMs of 16 GB each combine to make one region namespace of 32 GB. Hence, there are only two DAX devices created for four NVDIMMs.

 

  1. Return the acceleration and storage devices to operation by adding the devices that you removed back to the SDS.

 

For replacement using PFMP wizard see PowerFlex 4.x How to replace NVDIMM using PFMP Wizard

Affected Products

PowerFlex rack, PowerFlex appliance R650, Powerflex appliance R750, PowerFlex custom node R650, PowerFlex custom node R750
Article Properties
Article Number: 000217253
Article Type: How To
Last Modified: 18 Nov 2025
Version:  10
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