storage migration fails from snapshot LUN with CTK errors

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

In vpxa.log we will see below error with CTK during the storage vmotion from a snapshot lun to a production lun
 

Clone: 100% done.DISKLIB-CTK : ChangeTrackerCloneFD: invalid source CTK file descriptor.
DISKLIB-VMFS : "/vmfs/volumes/5be3231c-43fbc90e-3941-ecebb8975bbc/test/testclone1-flat.vmdk" : closed.
DISKLIB-VMFS : "/vmfs/volumes/5be3231c-43fbc90e-3941-ecebb8975bbc/test/testclone1-flat.vmdk" : open successful (1115137) size = 0, hd = 0. Type 3
DISKLIB-VMFS : "/vmfs/volumes/5be3231c-43fbc90e-3941-ecebb8975bbc/test/testclone1-flat.vmdk" : closed.
DISKLIB-LIB_CLONE : Failed to clone: Invalid change tracker error code (5948).
Failed to clone disk: Invalid change tracker error code (5948).

#### PRocess failed with "DISKLIB-LINK : DiskLinkNativeVmfsCloneExisting: Failed to create native clone. (24)."

 

Environment

VMware vSphere ESXi 6.7

Cause

the issue was a code change from 6.5 to 6.7 to no longer allow unclean CTK files to be migrated or cloned. Since this was a code change they determined it was not a bug in 6.7 but a change in behavior.

Resolution

it was not a bug in 6.7 but a change in behavior
Wordaround :

1. rm the change tracker file (filer-ctk.vmdk)
2. vi /vmfs/volumes/ssd-ds1/filer/filer.vmdk , comment out the change tracker line. 
3. Repeat clone (vmkfstools -i) 

Workaround:
instant recovery VMs created from storage snapshots will need to be powered on prior to them being able to be migrated using storage vMotion.

Additional Information

Impact/Risks:
Cold Storage vMotion fails while migrating from snapshot lun to production lun