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 Slow Storage vMotion from vSAN/iSCSI/NVMeoTCP to NVMeoTCP Volumes

Dag Kvello's profile image
Dag Kvello posted Mon October 27, 2025 08:25 AM

Firmware: 9.1.0.1

Network: 25GB Ethernet - MTU 9000

vSphere 8.0u3

I Provisioned identical volumes (1TiB, No space savings) to the host over both iSCSI and NVMeoTCP

Doing a migration from vSAN to IBM FS5300 (25GB Ethernet) i experience speeds similar to FCP (File Copy Protocol) instead for the expected speed of UDF (Unified Data Transport) protocol.

I set up both iSCSI and NVMeoTCP hosts against the same FS5300 and tried different source/target testing for storage migration (one VM 100GB used disk-space)

From vSAN to iSCSI it took around 4 minutes.

From iSCSI to NVMeoTCP took around 45 minutes.

From NVMeoTCP to NVMeoTCP took around 45 minutes

From NVMeoTCP to iSCSI took around 2.5 minutes

Digging through logs I found that svMotion used the UDF transport, so failing back to NCP was not the fault.

But, I finally did a VAAI primitives comparison and I noticed that the NVMe volume said "Clone Status: unsupported"

This explained the dismal performance...

Is this VAAI feature missing for NVMe volumes in 9.1.x ? or have i misconfigured something on the storage ?

(I did a check on a pure Fiberchannel FS5300 and noticed the same there for NVMeoFC volumes)

naa.60050768128104138000000000000179
   VAAI Plugin Name:
   ATS Status: supported
   Clone Status: supported
   Zero Status: supported
   Delete Status: supported
   Ex Clone Status: unsupported

eui.80000000000000090050760812810413
   VAAI Plugin Name:
   ATS Status: supported
   Clone Status: unsupported
   Zero Status: supported
   Delete Status: supported
   Ex Clone Status: unsupported

Evelyn Perez's profile image
Evelyn Perez

This VAAI command is supported on SCSI only.
It would never work between SCSI and NVMe
Storage Virtualize is running an earlier version of the NVMe spec and does not have support for VAAI clone status at this time.