Description

A new VM was created on IBM storage to isolate previous NetApp performance issues. 
relate to snapshot deletion :  MTV-4436

We are using a single 1TB VM with 360GB of baseline data. An fio script runs overnight to generate data automatically. Crucially, the data generation starts after the first snapshot is taken this ensures the first snapshot captures the 360GB baseline, while subsequent hourly snapshots capture the active changes. We will perform the cut-over in the morning. 

During the execution of TC 3.7 Warm Migration on this new setup, the migration failed completely during the CopyDisks phase.

Unlike the previous issue where migration was stuck on consolidation, this attempt failed with a critical authentication error, and the importer pod logs indicate that the expected snapshot could not be found on the source VM.

Steps to Reproduce

1. Environment: New source VM (ibm-fio-1tb-warm) created on IBM iSCSI Storage (PerfTest_VC7_1_ISCSI_17TB_IBM).

1. Plan: Warm Migration TC 3.7 initiated.

1. Phase: CopyDisks (specifically attempting to process checkpoint 3174-snapshot-2).

1. Failure: The importer pod failed to transfer data and exited immediately.

Observed Error

1. Migration Status Error (CR):
YAML
 

phase: CopyDisks
reasons:
- 'Unable to process data: Unable to transfer source data to target file:
  ServerFaultCode: The session is not authenticated.' 

2. Importer Pod Logs (importer-1vm-ibm-1tb...):
The logs show that while the VM was found and powered on, the specific snapshot ID requested by the controller did not exist on the VM at that moment.

I0128 11:04:16.614801 1 vddk-datasource_amd64.go:838] Creating VDDK data source: backingFile [[PerfTest_VC7_1_ISCSI_17TB_IBM] ibm-fio-1tb-warm/ibm-fio-1tb-warm_3.vmdk], currentCheckpoint [3174-snapshot-2]...
I0128 11:04:16.663050 1 vddk-datasource_amd64.go:497] VM 4235d4be-c305-56d4-0ed8-a6c19bca3468 found in datacenter Datacenter:ha-datacenter
I0128 11:04:16.664631 1 vddk-datasource_amd64.go:298] Current VM power state: poweredOn
E0128 11:04:16.668362 1 vddk-datasource_amd64.go:864] Could not find current snapshot 3174-snapshot-2: no snapshots for this VM
E0128 11:04:16.668376 1 importer.go:348] no snapshots for this VM 

• Analysis

• Snapshot Mismatch: The importer logic expected 3174-snapshot-2 to exist, but the VDDK call returned "no snapshots for this VM". This suggests a race condition where the snapshot might have been deleted (consolidated) by vCenter before the importer could attach to it, or the MTV controller state is out of sync with vSphere.

• Authentication Failure: The ServerFaultCode: The session is not authenticated suggests the VDDK connection to the host/vCenter was dropped or invalidated, possibly due to high load or a timeout on the ESXi host side during the snapshot operation.

Logs & Evidence

• Source VM: ibm-fio-1tb-warm

• Datastore: PerfTest_VC7_1_ISCSI_17TB_IBM

• Timestamp: Jan 28, 11:04:16 UTC

• Failing Component: Importer Pod / VDDK

the current plan is still present on cloud15 for live debug marnold@redhat.com 

plan/ns name :  1vm-ibm-1tb-366gb-usage-dynamic-fio-warm-tc3-7
full logs path :  /home/kni/Tzahi_MTV/mtv-debug-1vm-ibm-1tb-366gb-usage-dynamic-fio-warm-tc3-7-20260128-093013