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Support for NVMe hot-plug on VMware vSphere 6.x and VMware vSAN 6.x
10 NVMe Hot-Plug on Dell EMC PowerEdge servers running VMware vSphere or vSAN | Technical white paper |
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3.3 Perform orderly removal of an NVMe device on a VSAN cluster
VMware vSAN is a software-based storage solution for VMware hyperconverged solutions. Embedded in the
hypervisor and leveraging industry-standard servers, vSAN delivers flash-optimized, high-performance
computation and storage for hyperconverged infrastructures. vSAN can make use of NVMe devices in both
cache and capacity tier.
Dell EMC has vSAN readynodes that support NVMe devices as both a cache tier and a capacity tier providing
every available NVMe solution. For more information on the vSAN readynodes supported by Dell EMC, see
VMware Compatibility Guide
Listed below are recommendations to perform orderly removal of an NVMe device from a vSAN cluster:
• If the NVMe device that is to be removed by hot removal is in the cache tier, the overall process
depends on the use case. Ensure to evacuate the data before removing the disk as the diskgroup will
be earased when the NVMe device is hot removed.
• If the NVMe device that is to be removed by hot removal is in the capacity tier, ensure that the device
is accessed carefully as it depends upon FTT (Failure to Tolerate) and other parameters. For more
information on general recommendations for removing a disk from vSAN host, see VMware
Knowledge Base article 2150593.
3.4 Perform orderly removal of an NVMe device configured as a host
cache device
Follow the steps:
1. Check the NVMe device usage. Go to vCenter Server > Host > Configure. Under the Storage tab,
select Host Cache Configuration. The NVMe device utilized as a host cache is displayed.
Identifying the NVMe device usage
2. Edit the host cache configuration for the NVMe device to set the host cache space to zero bytes. This
ensures no space from NVMe datastore is used as host cache space.
Host Cache Space set to zero.
3. Unmount the datastore. This can be done on the GUI or the CLI using the command:
esxcli storage filesystem unmount -l NVMe_Host_cache_DS