Sep 23

IC92873: SOME EXECUTABLE FILES FOR WINDOWS SERVICES NOT BACKED UP ON WINDOWS 8 AND WINDOWS SERVER 2012

APAR Comments Off on IC92873: SOME EXECUTABLE FILES FOR WINDOWS SERVICES NOT BACKED UP ON WINDOWS 8 AND WINDOWS SERVER 2012

Error description

  • Some executable files (xxxxxxxx.exe) for Windows NT style
    services are excluded from backup. This can impact system
    restores such that certain applications or services will not
    start.
    
    Beginning with Microsoft Windows Vista and Microsoft Windows
    Server 2008, executables for Windows NT style services are
    treated as part of the VSS System Writer portion of system
    state. Thus the Tivoli Storage Manager backup-archive client
    backs up these files as part of system state and omits them from
    other file system backup operations.
    
    Beginning with Microsoft Windows 8 and Microsoft Windows Server
    2012, these executable files remain a part of the VSS System
    Writer, but are not considered to be part of the recoverable
    system state. Therefore the correct behavior for Tivoli Storage
    Manager is to include these files during file system incremental
    backup but not during system state backup.
    
    For example, if the Tivoli Storage Manager Backup-Archive Client
    scheduler service is installed on Windows Vista, Windows 7,
    Windows 8, Windows Server 2008, Windows Server 2008 R2, or
    Windows Server 2012, then the executable file for the scheduler
    service (dsmcsvc.exe) is treated as part of the VSS System
    Writer. However, it is only treated as part of recoverable
    system state on Windows Vista, Windows 7, Windows Server 2008,
    and Windows Server 2008 R2. dsmcsvc.exe should not be treated as
    part of recoverable system state on Windows 8 and Windows 2012.
    
    The following table summarizes the correct behaviors for backup
    of these executable files:
    
    Table 1:
    
                            PART OF         BACKED UP AS PART OF
     OPERATING SYSTEM    SYSTEM WRITER   SYSTEM STATE   FILE SYSTEM
     ----------------    -------------   ------------   -----------
     Windows Vista            Yes            Yes            No
     Windows 7                Yes            Yes            No
     Windows 8                Yes            No             Yes
     Windows Server 2008      Yes            Yes            No
     Windows Server 2008 R2   Yes            Yes            No
     Windows Server 2012      Yes            No             Yes
    
    The following table summarizes the problem behavior for these
    executable files on the affected operating systems:
    
    Table 2:
    
                            PART OF         BACKED UP AS PART OF
     OPERATING SYSTEM    SYSTEM WRITER   SYSTEM STATE   FILE SYSTEM
     ----------------    -------------   ------------   -----------
     Windows 8                Yes            No             No
     Windows Server 2012      Yes            No             No
    
    The Backup-Archive Client behavior should be corrected so that
    these executable files are backup up as part of the file system
    backup operations as shown in Table 1 above.
    
    Tivoli Storage Manager Versions Affected:
    Tivoli Storage Manager client versions 6.3.1.x (x >= 1) and
    6.4.0.x (x >= 1) on Windows 8 and Windows Server 2012
    
    Note: Support for Windows 8 and Windows Server 2012 was
    added as of versions 6.3.1.0 and 6.4.0.0.
    
    Initial Impact:
    Medium
    
    Additional Keywords:
    zz63 zz64 TSM exe writers vss IC89320
    
    | MDVREGR 6.3.1.1-TIV_5698MCL |
    | MDVREGR 6.4.0.1-TIV_5698MCL |

     

Local fix

  • Downgrade client code to 6.4.0.0
    or make a copy of missing executables to a new path and
    backup/archive client filesystem backup will back them up
    under the secondary path
    
    or if on version 6.3.1.x;
    
    Downgrade client code to 6.3.1.0
    or make a copy of missing executables to a new path and
    backup/archive client filesystem backup will back them up
    under the secondary path

written by Bosse

Sep 23

Amount of data backed up increases significantly after VM disk resizing

VE Comments Off on Amount of data backed up increases significantly after VM disk resizing

Problem(Abstract)

After a disk of a VM guest is resized, the amount of data backed up by a full VM incremental of the guest machine increases significantly.

Symptom

Example of change follows.

Before: Disk size = 1.17TB Amount of data backed up by full vm incremental backup = 12GB
After: Disk size = 1.46TB Amount of data backed up by full vm incremental backup = 363GB

Cause

Change block tracking corrupted.

 

Resolving the problem

Change Block Tracking needs to be reset on the VMWare guest machine. Follow the steps below.

 

  1. Shutdown the VMware guest.
  2. Disable change block tracking for the guest
  3. Start the guest
  4. Shutdown the guest again
  5. Enable change block tracking
  6. Start the guest.

Refer to VMware article    1031873 for more information on enabling Changed Block Tracking (CBT) on virtual machines.

written by Bosse

Sep 23

Expiration of IFFull and IFincremental VM backups

VE Comments Off on Expiration of IFFull and IFincremental VM backups

The first incremental-forever-incremental backup of a VM guest will be an an incremental-forever-full backup. The “query vm” command will shows the type as IFFULL. For example :

dsmc q vm my-test-vm -ina ...  #      Backup Date       Mgmt Class  Size         Type   A/I Virtual Machine ---  -------------------  ----------  -----------  ------ --- ---------------   1  08/01/2013 11:13:10  VEMGMT         11.71 GB  IFFULL  A  MY-TEST-VM
Subsequent incremental-forever-incremental backups will then be incremental. The “query vm” command will shows the type as IFINCR. For example :
dsmc q vm my-test-vm -ina ...  #      Backup Date       Mgmt Class  Size         Type   A/I Virtual Machine ---  -------------------  ----------  -----------  ------ --- ---------------   1  08/01/2013 11:13:10  VEMGMT         11.71 GB  IFFULL  I  MY-TEST-VM   2  08/02/2013 11:57:13  VEMGMT         11.71 GB  IFINCR  A  MY-TEST-VM
Note that the IFFULL backup becomes inactive (I) and the IFINCR backup is then the active version (A). In a case where VEMGMT managament class is configured with verexists=5, each subsequent IFINCR backup inactivates the previous one. After the 5th backup, the “query vm” will show one IFFULL backup and 4 IFINCR backups. For example :
dsmc q vm my-test-vm -ina ...  #      Backup Date       Mgmt Class  Size         Type   A/I Virtual Machine ---  -------------------  ----------  -----------  ------ --- ---------------   1  08/01/2013 11:13:10  VEMGMT         11.71 GB  IFFULL  I  MY-TEST-VM   2  08/02/2013 11:57:13  VEMGMT         11.71 GB  IFINCR  I  MY-TEST-VM   3  08/03/2013 14:17:18  VEMGMT         11.71 GB  IFINCR  I  MY-TEST-VM   4  08/04/2013 11:26:31  VEMGMT         11.71 GB  IFINCR  I  MY-TEST-VM   5  08/05/2013 11:32:26  VEMGMT         11.71 GB  IFINCR  A  MY-TEST-VM
Note that the last IFINCR backup is now the active version and all previous IFFULL and IFINCR backups are inactive versions. Continuing with this example, and still using the VEMGMT managament class configured with verexists=5, any subsequent backup will expire the oldest backup as only 5 versions should be kept. For example, if another IFINCR backup is done, the IFFULL (oldest backup) is expired. After this backup, the “query vm” will show 5 IFINCR backups. For example :
dsmc q vm my-test-vm -ina ...  #      Backup Date       Mgmt Class  Size         Type   A/I Virtual Machine ---  -------------------  ----------  -----------  ------ --- ---------------   1  08/02/2013 11:57:13  VEMGMT         11.71 GB  IFINCR  I  MY-TEST-VM   2  08/03/2013 14:17:18  VEMGMT         11.71 GB  IFINCR  I  MY-TEST-VM   3  08/04/2013 11:26:31  VEMGMT         11.71 GB  IFINCR  I  MY-TEST-VM   4  08/05/2013 11:32:26  VEMGMT         11.71 GB  IFINCR  I  MY-TEST-VM   5  08/06/2013 11:15:47  VEMGMT         11.71 GB  IFINCR  A  MY-TEST-VM
Notes :

  • Despite the IFFULL backup being expired, it is still possible to restore the VM guest using the IFINCR backups due to the nature of the Incremental forever backup strategy.
  • The space occupied by the VM backups in an active-data storage pool will be equivalent to the amount of in-use blocks on the Virtual Machine, even when the IFFULL backup is inactive or expired.
  • If an activedata storage pool is used and backups of virtual machines are stored in the activedata storage pool, adequate space to the active-data pool should be allocated. The space allocation can be estimated based on the size of the original IFFULL backup.

Related information

Query amount of data backup up by IFINCR Query amount of data backup up by IFFULL

written by Bosse