IT32170: FULL VM BACKUP MIGHT FAIL WITH ANS4174E AND RC=7334 WHEN THE CBTINFO CANNOT BE OBTAINED BECAUSE THERE IS AN EXISTING SNAPSHOT

APAR status

• Closed as program error.

Error description

• When trying to backup a VM which has an existing snapshot and
  the CBT information could not be obtained the Incremental
  backups will fail and will show the following warning message :
  
  ANS9419W VMware Changed Block Tracking (CBT) cannot be enabled
  or reset for virtual machine 'VM_NAME' due to an existing
  snapshot. Full VM backup continues, and includes both used and
  unused areas of the disk.
  
  This message indicates that a full backup will be attempted
  because the CBT could not be reset because there is an existing
  snapshot however the full backup will also fail with the below
  error :
  
  ANS4174E Full VM backup of VMware Virtual Machine 'VM_NAME'
  failed with RC=7334 mode=Incremental Forever - Full, target node
  name='DC_NODE', data mover node name='DM_NODE'
  
  The manual VM backup with "-mode=iffull" will fail with the same
  error message and service trace will show the following :
  
  01/15/2020 1357.171 [004652] [1764] :
  ..\..\common\vm\vmvisdk.cpp(9877): visdkVmHasSnapshots: We have
  one or more snapshot(s) on vmMoRef 'vm-326272'
  01/15/2020 1357.171 [004652] [1764] :
  ..\..\common\vm\vmvisdk.cpp(9878): <========= Exiting
  visvisdkVmHasSnapshotsdkGetVmSnapshotMoRef()
  01/15/2020 1357.171 [004652] [1764] :
  ..\..\common\vm\vmbackvddk.cpp(16450):
  vmVddkFullVMPrePareToOpenVMDKs: pre-existing snapshot found when
  enabling/resetting CBT
  01/15/2020 1357.171 [004652] [1764] :
  ..\..\common\vm\vmbackvddk.cpp(16472):
  vmVddkFullVMPrePareToOpenVMDKs: Snapshot exists so cannot enable
  CBT; Failing backup.
  01/15/2020 1357.171 [004652] [1764] :
  ..\..\common\vm\vmbackvddk.cpp(11181): vmVddkBackupVM(): after
  vmVddkFullVMPrePareToOpenVMDKs vmEntryP->vmAppProtection is 0
  01/15/2020 1357.171 [004652] [1764] :
  ..\..\common\vm\vmbackvddk.cpp(14440): =========> Entering
  VmBackupVMCleanup()
  
  The ANS9419W message is misleading and should be updated because
  it states that a Full Backup will be attempted and then this
  Full backup attempt fails reporting the above errors.
  
  =======================
  Affected versions:
  IBM Spectrum Protect for Virtual Environments - Data Protection
  for VMware 7.1.x and 8.1.x that has the fix for APAR  IT26261 on
  all supported Windows and Linux platforms.
  =======================
  Initial Impact: Medium
  =======================
  Additional Keywords:
  TS003166074 tsm tdp ve vmware linux windows backup vm spectrum
  protect CBT reset existing snapshot
  

Local fix

• 1- Remove the existing snapshots and perform CBT reset as per
  the instructions in the below link and run another full VM
  backup for the affected VM:
  
  https://www.ibm.com/support/pages/backup-vmware-vms-can-be-corru
  pted-and-thus-not-restorable-if-snapshot-exists-when-cbt-enabled
  
  2- If it is a must to keep existing snapshots for the VM then
  set the below option in the DM options file to force a full
  backup of the VM
  
  VMNOCBTCONTINUE YES
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Data Protection for VMware versions 8.1.7, 8.1.8 and 8.1.19  *
  * running on all Microsoft Windows x64 and Linux x86           *
  * platforms.                                                   *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See ERROR DESCRIPTION                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * This issue is projected to be fixed in the Data Protection   *
  * for VMware Data Mover version 8.1.10 on Windows x64 and      *
  * Linux x86 platforms.                                         *
  * Note 1: This is subject to change at the discretion of IBM.  *
  ****************************************************************
  

Problem conclusion

• The message has been updated.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  IT33279

Modules/Macros

• dsmagent
  

Fix information

• Fixed component name

  TSM FOR VE DP V

• Fixed component ID

  5725TVEVM

Applicable component levels