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DPM 2007 tape retention setup .. RRS feed

  • Question

  • I have DPM 2007 installed currently with Protection Groups setup for each type of data EG. Exchange, SQL, Files - just wondering what is the best way to setup my Protection Groups - short/long term goal settings.

    My backup requirements are:

    File to disk - 7 days just before a recovery point

    File to tape - weekly to tape for 4 weeks then once per month for 3 months - I would like to have this tape marked and stored as a quarterly backup (the main issue I am having is how to identify the tapes/see what it contains and when it is ready for off-site storage)

     

    Thanks

    • Moved by MarcReynolds Tuesday, March 1, 2011 1:16 PM (From:Data Protection Manager)
    Tuesday, March 1, 2011 3:02 AM

Answers

  • As stated above, the length of time DPM will use a tape is generally time based unless the tape gets filled before the time elapses.  For a 30 day retention period, dpm will only write to the tape for (30*.15 = 4.5 days) or one weekly backup. If you want DPM to use the tape for a longer period of time adjust the TapeWritePeriodRatio accordingly up to 100%.  Keeping in mind that the setting effects all PG's and all retention goals.  DPM 2012 will provide more granular control.
    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Wednesday, March 9, 2011 5:28 AM

All replies

  • Hi,

    To have any control on how long a tape will be used before DPM marks it offsite ready, you need to enable the tape co-location feature.  Once that is enabled, you can can control how long the weekly backup tapes get written to before being marked offsite ready by adjusting the WritePeriodRatio setting.

    DPM 2007 - http://technet.microsoft.com/en-us/library/cc964296.aspx
    DPM 2010 - http://technet.microsoft.com/en-us/library/ff399230.aspx

    Rotating Tapes Offsite
    ======================

    DPM Administrator Console indicates when a tape in the library should be removed and stored in your archive location by displaying a green icon in the Offsite Ready column. You can also view all tapes ready to be stored offsite in the Tape Management Report. The Tape Management Report lists tapes that will be due for offsite storage in the upcoming period of time selected for the report.

    When the data on a tape expires, return the tape to the tape library. Expired tapes not returned to the tape library will be marked as "overdue" in the Tape Management Report. Overdue tapes expired during an earlier reporting period. Expired tapes should be returned to the tape library for reuse.

    When tape colocation is enabled, a tape on to which offsite backup is written will not be shown as Offsite Ready unless one of the following conditions are met:

     - The tape is full.
     - One of the datasets has expired.
     - Write-period ratio has been crossed. (By default, this is first backup time + 15 per cent of retention range.)

     

    Enabling Data Co-Location on DPM

    a. Open DPM Management Shell.
    b. Set-OptimizeTapeUsage to True using the Set-DPMGlobalProperty cmdlet.

           Set-DPMGlobalProperty -DPMServerName <name of DPM server> -OptimizeTapeUsage $True

     

    WritePeriodRatio:

    TapeWritePeriodRatio is a property that can be set when colocation is enabled on tape.  In case of non-colocated ProtectionGroup, the tape becomes marked as “offsite ready” as and when it is written on to.
     
    Colocation is enabled for PGs of identical retention periods.  However the times at which data are backed to  tape may vary for each collocated PG. In such cases, this parameter helps the user to decide how long to write to tape before sending the tape offsite, even though it might not be full.

    WritePeriodRatio indicates the number of days for which data can be written on to a tape as a ratio of the retention period of the first data set written to the tape.

    WritePeriodRatio value can be between 0.0 to 1.0
    Default value is 0.15 (i.e. 15%)

    TapeWritePeriodRatio is a global property for the DPM which needs to be set using DPM power shell command. Here is the command to set it.

        Set-DPMGlobalProperty –DPMServerName <dpm server name> -TapeWritePeriodRatio <fraction>


    For example, if the retention period for the first data set written to a tape is 28 days, and you set the Write-Period ratio as 0.15, data will be written to the tape for 4.2 days from the day on which the first data set was written to the tape. After this period, the tape will be marked as offsite ready and no more data will be written to that tape until all recovery points have expired on that tape.


    TapeExpiryTolerance:

    Indicates the number of days over the furthest expiry date among all datasets on the tape that the tape will continue to be used.

    The default value is 17 percent.

    This registry values is located under HKLM\Software\Microsoft\Microsoft Data Protection Server\1.0\Colocation.
                                                     TapeExpiryTolerance:REG_DWORD:0x11

     

    Download the tape offsite calculator spreadsheet from here to help you adjust the above settings to meet your needs: http://cid-885774776d4f197a.office.live.com/self.aspx/Public/tape-offsite-ready-calculator.zip?wa=wsignin1.0&sa=194257143

     


    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Tuesday, March 1, 2011 5:40 PM
  • Thanks, so just to clarify. I already have co-location enabled. Do I need to set the WritePeriodRatio? What would I set this too for the long term requirements of: weekly to tape for 4 weeks then once per month for 3 months? Will DPM only mark the tapes as Off-Site once it hits the 3 month mark? Will DPM only use the tapes it needs autpmically space wise? EG will fill up the tape then move to the next? Thanks
    Wednesday, March 9, 2011 4:14 AM
  • As stated above, the length of time DPM will use a tape is generally time based unless the tape gets filled before the time elapses.  For a 30 day retention period, dpm will only write to the tape for (30*.15 = 4.5 days) or one weekly backup. If you want DPM to use the tape for a longer period of time adjust the TapeWritePeriodRatio accordingly up to 100%.  Keeping in mind that the setting effects all PG's and all retention goals.  DPM 2012 will provide more granular control.
    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Wednesday, March 9, 2011 5:28 AM
  • Thanks, so if I start with fresh tapes - and long term backups to tape are set to weekly for a month then monthly for 3 months - am I right to assume DPM will assign all the tapes it needs using the full space and then mark those tapes as Off-site after 3 months? Can I just remove the tapes after 3 months and start the process again with new tapes?
    Wednesday, March 16, 2011 12:46 AM