IT24024: ANS2745E ON 'BACKUP VM' OF HYPER-V GUEST

IBM Spectrum Protectâ„¢ Client 8.1.6 Downloads and READMEs

APAR status

• Closed as program error.

Error description

• The Hyper-V guest 'BACKUP VM' can stop with :
  
  ANS4308E Full VM backup of 'Hyper-V' Virtual Machine
  '<guestname>' failed with RC=7136 mode=Incremental Forever -
  Full, target node name='<target node>', data mover node
  name='<data mover node>'
  ANS1228E Sending of object '<guestname>' failed.
  ANS2745E An assigned virtual disk to Hyper-V Virtual Machine
  '<guestname>' cannot be found.
  
  This can be due to the guest having been migrated with a
  non-Microsoft tool which changes slightly the contents of the
  vhdx disk header which is unexpected by the client when
  validating the disk.
  
  To check if the guest disk is affected by this defect :
  
  1. Halt the guest
  2. Use a hex editor to open the vhdx file
  3. The first bytes will display if the vhdx file was
  created/migrated
     with a Microsoft tool. If it is the case it will look like :
  
     Offset(h) 00 01 ... 0F
      00000000 76 00 ... 00  vhdxfileM.i.c.r.
      00000001 6F 00 ... 00  o.s.o.f.t. .W.i.
      00000002 6E 00 ... 00  n.d.o.w.s.
  
  4. If the above location displays another name, go to
  offset(hex;h) 0003002C
  
     Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
      00030020 00 00 30 00 00 00 00 00 00 00 10 00 01 00 00 00
  
     ==> The above example displays at offset(h) 0003002C the
  value '01'
         which is what the client is expecting.
         If that value is different, the 'BACKUP VM' stops with
  ANS2745E.
         This is incorrect and the client should not fail
  validation about that offset value.
  
  IBM Spectrum Protect Versions Affected:
  All supported versions of the IBM Spectrum Protect for Virtual
  Environments - Data Protection for Hyper-V on Windows
  
  Customer/L2 Diagnostics :
  
  A data mover client HYPERV trace will show the validation
  failure :
  
  <timestamp> [PID] [TID] : ..\..\common\vm\HyperV\
     hypervcommon.cpp(2427): ENTER =====> HyperVVM::ValidateVM():
  .. : ENTER =====> Vhdx::Init()
  .. : ENTER =====> Vhdx::LoadAndCheckFileIdentifier()
  .. : EXIT  <===== Vhdx::LoadAndCheckFileIdentifier()
  .. : ENTER =====> Vhdx::LoadAndCheckVhdxHeaders()
  .. : Vhdx::LoadAndCheckVhdxHeaders(): Found valid header 1
  .. : Vhdx::LoadAndCheckVhdxHeaders(): Found valid header 2
  .. : Vhdx::LoadAndCheckVhdxHeaders(): Header 2 selected as most
  recent
                                        version
  .. : EXIT  <===== Vhdx::LoadAndCheckVhdxHeaders()
  .. : ENTER =====> Vhdx::LoadAndCheckRegionTable()
  .. : ENTER =====> Vhdx::ParseRegionTableEntry()
  .. : EXIT  <===== Vhdx::ParseRegionTableEntry()
  .. : Vhdx::LoadAndCheckRegionTable() Failed to read region
  table entry.
  .. : EXIT  <===== Vhdx::LoadAndCheckRegionTable()
  .. : EXIT  <===== Vhdx::Init()
  <timestamp> [PID] [TID] : ..\..\common\vm\HyperV\
     hypervcommon.cpp(2501): HyperVVM::ValidateVM(): Unable to
  open disk
     to check disk IDs rc=7136
  <timestamp> [PID] [TID] : ..\..\common\vm\HyperV\
     hypervcommon.cpp(2427): EXIT  <===== HyperVVM::ValidateVM():,
     rc = 7136
  
  Initial Impact: Medium
  
  Additional Keywords: Hyperv tdp4ve tsm4ve vhdx migrate
  

Local fix

• 1. Halt the guest.
  2. Use a hex editor to open the vhdx file.
  3. Go to offset(h) 0003002C change the value to '01'.
  4. Close the hex editor and restart the guest.
     The backup vm should now complete successfully.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * IBM Spectrum Protect for Virtual Environments: Data          *
  * Protection for Microsoft Hyper-V Data Mover v7.1.6 - v7.1.8  *
  * and v8.1.0 - v8.1.4 on Windows Server 2012/2016 (R2).        *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See ERROR DESCRIPTION                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * This issue is projected to be fixed in the Backup-Archive    *
  * Client version 8.1.6 on all Microsoft Windows x64 platforms  *
  * Note 1: The Backup-Archive Client is a part of the Data      *
  * Protection for Microsoft Hyper-V. In Data Protection for     *
  * Microsoft Hyper-V environments, the Backup-Archive Client is *
  * also known as the data mover.                                *
  * Note 2: This is subject to change at the discretion of IBM.  *
  ****************************************************************
  

Problem conclusion

• DP for Microsoft Hyper-V can fail to back up Hyper-V virtual
  machine that was converted from VMware ESX server using QEMU
  free disk image utility (
  https://blogs.msdn.microsoft.com/virtual_pc_guy/2015/06/22/handy
  -tool-for-converting-kvm-vmware-images-to-hyper-v/). When
  converting a VMDK to VHDX the resulting VHDX's Region table has
  a small *error*. This bug has been reported to Ubuntu's QEMU
  project as bug number 1749016. There is no guarantee they will
  ever fix their VHDX segment of their virtualization disk image
  converter to set the Region Entries' Required bit to 1
  correctly. Our code has been modified to ignore this bit.
  

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:

Modules/Macros

• DSMC     DSM      DSMCSVC
  

Fix information

• Fixed component name

  TSM CLIENT

• Fixed component ID

  5698ISMCL

Applicable component levels

• R81W PSY

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