File Server Long Running Incremental

Last post 04-23-2018, 3:21 PM by ignesi. 7 replies.
Sort Posts: Previous Next
  • File Server Long Running Incremental
    Posted: 04-15-2018, 1:23 PM


    I have a File Server running as a VM (Win 2008 R2) configured with the File Server agent for backups and eventually archiving.

    The client is configured to make use of the Optimized Scan method which generally works fine.

    I have one issue though with a long running incremental after the weekly synthetic full backup. The following incremental run is performing as usual again.

    Sizes are reported application size.

    Inc before Syn Full1hr100GB

    Syn Full3hr5.4TB

    Incr after Syn Full15hr3.2TB


    Not sure why the run after the Synthetic Full would state that 3.2TB of data has changed although with deduplication only a couple of GB are actually written to disk.

    Any ideas of what could cause this.

    Much appreciated.

  • Re: File Server Long Running Incremental
    Posted: 04-16-2018, 3:34 AM

    I don't know which SP you are running, but there are fixes regarding this problem.


    Size of Windows File System incremental backup after a synthetic full may be as big as a full backup. Hotfix 2761

    Please install latest hotfix pack

  • Re: File Server Long Running Incremental
    Posted: 04-16-2018, 11:17 AM

    Sounds like an AV issue. Can you check your exceptions. 

  • Re: File Server Long Running Incremental
    Posted: 04-16-2018, 2:56 PM
    • Aplynx is not online. Last active: 04-25-2018, 11:12 AM Liam
    • Top 10 Contributor
    • Joined on 05-04-2010
    • New Jersey
    • Expert
    • Points 1,286

    Is it always on the same backup time? Can you modify the backup to try to launch the incremental on a day other then what it is running on now? This may be something 3rd party modifying change journal and causing all the files to be seen as new. Recursive scan would be another way to test this. 


  • Re: File Server Long Running Incremental
    Posted: 04-19-2018, 8:23 AM


    Running v11 SP10.

    Don't have that hotfix installed.

    The backup was changed from Sun 8pm to Sat 8pm with the same result.


    I have noticed the option Synchronize Source Files and Backup Index in the Advanced Options of the subclient configuration.

    It mentions that there might be an increase in scan time if this is enabled.


    Please comment.


  • Re: File Server Long Running Incremental
    Posted: 04-19-2018, 8:32 AM

    Synchronize Source Files and Backup Index might have impact on the job duration, but I would not expect that the backup size would increase so significantly for only the first incremental after a synthetic full.

    My advise is, update to SP11 with latest hotfix pack, high probability that this solves your issue.

  • Re: File Server Long Running Incremental
    Posted: 04-22-2018, 8:18 PM
    • aldog24 is not online. Last active: 22 Apr 2018, 10:00 PM aldog24
    • Top 500 Contributor
    • Joined on 03-16-2017
    • Sydney, Australia
    • Novice
    • Points 54

    Hello ignesi,


    We may need a support ticket to invesitgate this one further, but it does sound like it is being caused by the feature true up.


    Please see:


    "Note: By default, the synchronization runs after every incremental job that runs after a synthetic full backup."


    If the scan is what is delaying the job, this can be rectified using the following additional key: bIgnoreTrueUpChangeTimeCheck. Please review the documentation above for how to configure this setting.


    Please let us know if this resolves your issue.


    Kind regards



  • Re: File Server Long Running Incremental
    Posted: 04-23-2018, 3:21 PM

    I have disabled that option before the weekend's full backup.

    The behaviour was the same.

    Prior to Full

    Scan Time30min

    Backup Time44min

    After Syn Full

    Scan Time3hr 26 mins

    Backup Time10hrs 11 mins

    Will that additional setting have an effect if the setting is disabled?

The content of the forums, threads and posts reflects the thoughts and opinions of each author, and does not represent the thoughts, opinions, plans or strategies of Commvault Systems, Inc. ("Commvault") and Commvault undertakes no obligation to update, correct or modify any statements made in this forum. Any and all third party links, statements, comments, or feedback posted to, or otherwise provided by this forum, thread or post are not affiliated with, nor endorsed by, Commvault.
Commvault, Commvault and logo, the “CV” logo, Commvault Systems, Solving Forward, SIM, Singular Information Management, Simpana, Commvault Galaxy, Unified Data Management, QiNetix, Quick Recovery, QR, CommNet, GridStor, Vault Tracker, InnerVault, QuickSnap, QSnap, Recovery Director, CommServe, CommCell, SnapProtect, ROMS, and CommValue, are trademarks or registered trademarks of Commvault Systems, Inc. All other third party brands, products, service names, trademarks, or registered service marks are the property of and used to identify the products or services of their respective owners. All specifications are subject to change without notice.
Copyright © 2018 Commvault | All Rights Reserved. | Legal | Privacy Policy