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robson_correa1's avatar
robson_correa1
Level 3
10 years ago

Backup - Disk Dynamic Hyper-V Windows 2012 via Client

Good morning Mariane, can you help me? I'm having trouble backing up a client that has dinamic disk. My environment: Master: 7.6.02 OS: Linux red. hat 6 - Veritas Cluster Medias Servers: ...
7.6
Backing Up
Backup and Recovery
Linux
NetBackup
Restore
  • Marianne's avatar
    Marianne
    10 years ago

    It seem we have missed this:

    I run the backup via client installed on this virtual machine....

    So, this should be treated as normal client backup with MS-Windows policy type? Not Hyper-V?

    It seems that the backup has actually completed, but failed right at the end when snapshot info stored on the master server could not be obtained.

    Info bpfis(pid=3452) done. status: 4207: Could not fetch snapshot metadata or state files

    I had a similar problem recently when my laptop could not connect to the old demo master in the environment (current master/media was only listed and secondary Server).

    You need to ensure connectivity between master and client (port connectivity and forward/reverse name lookup) or else disable snapshot backups.

    See my post over here: https://www-secure.symantec.com/connect/forums/failing-backups-status-156#comment-10637661 

    About the dynamic volume and this error: 

    ERR - failure reading file: D:\BACKUP\MSSQL\bd_cob.bkp (WIN32 2: The system cannot find the file specified. )
2/14/2015 7:28:07 AM - Error bpbrm(pid=22237) from client SDOIINT01.oiinternet.corp: ERR - Snapshot Error while reading file: GLOBALROOT\Device\HarddiskVolumeShadowCopy6\BACKUP\MSSQL\bd_cob.bkp

    You need to speak to SQL Admins - seems the may have deleted the .bkp file before NBU backup was completed. 
    You also need to co-ordinate with them to ensure that NBU backup does not start before SQL dump is 100% completed.

    Why not rather use the NBU for SQL agent? The agent ensures a one-step backup and one-step restore.
    No need to co-ordinate SQL dumps and NBU backups, no multi-step backup and restore process, no need to manually take care of disk space on the backup volume.

RiaanBadenhorst's avatar
RiaanBadenhorst
Level 6
10 years ago

Hello

 

(Ma)Riaan(ne) here.

 

Its a limitation of HyperV, not NetBackup. Please see this article https://msdn.microsoft.com/en-us/library/dd405549%28v=vs.85%29.aspx

 

Backing Up the Virtual Machines

Hyper-V uses one of two mechanisms to back up each VM. The default backup mechanism is called the "Saved State" method, where the VM is put into a saved state during the processing of the PrepareForSnapshot event, snapshots are taken of the appropriate volumes, and the VM is returned to the previous state during the processing of the PostSnapshot event.

The other backup mechanism is called the "Child VM Snapshot" method, which uses VSS inside the child VM to participate in the backup. For the "Child VM Snapshot" method to be supported, all of the following conditions must be met:

  • Backup (volume snapshot) Integration Service is installed and running in the child VM. The service name is "Hyper-V Volume Shadow Copy Requestor".

    Windows 2000:  Backup Integration Service is not supported.

  • The child VM must be in the running state.
  • The Snapshot File Location for the VM is set to be the same volume in the host operating system as the VHD files for the VM.
  • All volumes in the child VM are basic disks and there are no dynamic disks.
  • All disks in the child VM must use a file system that supports snapshots (for example, NTFS).

In general, the process for backing up VMs is the same as described in Overview of Processing a Backup Under VSS. The unique behavior happens when the Hyper-V VSS writer (part of the "Hyper-V Virtual Machine Management" service) processes the PrepareForSnapshot event. If the backup was done using the "Child VM Snapshot" method, there is additional processing done but it is not visible to the child VM.

The following procedure describes how to back up VMs.