Non-Exclusive VSS Exchange Backups

Posted on 2011-04-24
Last Modified: 2012-05-11
I am running an Exchange-aware backup program (SonicWall CDP Version 6.0) that uses the MS VSS writer and truncates the Exchange log files.  Full Exchange backups are run every couple of hours and finish quickly with little disk space usage due to deduplication.  I also run an image backup solution (Acronis Version 10) that uses Volume Snapshotting but does not truncate the logs or use Application Snapshotting. I had intended to always turn off all VSS capability in the Acronis but have inadvertantly run some image backups that snapshot the volume containing the Exchange database.  My concern is whether snapshots from the image backup software might potentially confuse the primary Exchange backup software.  Given that the Acronis does not take application snapshots, should my Exchange backups still be ok?  It is a long and painful procedure to reseed the Exchange backup so I'd like to avoid doing so if it is not necessary.  

On that subject, can someone verify explain how VSS backups work in Exchange?  Does the backup compare the current state of the EDB and log files against what is already backed up on backup media?  Or does the system remember the state of the last snapshot and only record what has changed since that point irrespective of what is on the backup media?  Is it safer to always take full image backups of the volume containing the Exchange Store rather than incrementals/differentials?  Or does this vary entirely depending on the backup program?  I have customers using Acronis, Backup Exec System Recovery (which is Exchange-aware) and the SonicWall CDP.  

Also, can anyone suggest any easier method to validate an Exchange backup set than what I use?  To be safe I restore the entire EDB file and all log files to disk and then run ESEUTIL against these files.  This can take hours which is a deterrent to frequent integrity checks.

If I am asking too many questions in this one post then please let me know so that I can break up this question in order to reward points appropriately.


Question by:Qualitycomputer
    LVL 17

    Accepted Solution

    1. You should be fine running your System snapshots via Acronis and Exchange aware VSS backups via SonicWall.  I think Acronis leverages MS VSS as well so at times you may experience resource based issues that could cause one backup type or the other to fail, however, it should be able to recover at the next backup point.  So based upon the above you may want to configure your backup products to notify you upon failure of any job so that you are aware that its taken place and can then adjust/monitor appropriately.

    2. Good article on MS VSS

    3. You could use a 3rd party product that will let you mount the offline database to prove its viable. If you want more information check my profile for contact information


    Author Closing Comment

    Thanks for that input.  Between your response and the article link I think I am in good shape.
    LVL 17

    Expert Comment

    Happy to be of assistance, thanks for the points and have a great week!

    Featured Post

    Why do Marketing keep bothering you?

    Is your marketing department constantly asking for new email signature updates? Are they requesting a different design for every department? Do they need yet another banner added? Don’t let it get you down! There is an easy way to manage all of these requests...

    Join & Write a Comment

    Use these top 10 tips to master the art of email signature design. Create an email signature design that will easily wow recipients, promote your brand and highlight your professionalism.
    Not sure what the best email signature size is? Are you worried about email signature image size? Follow this best practice guide.
    In this video we show how to create a mailbox database in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Servers >> Data…
    To add imagery to an HTML email signature, you have two options available to you. You can either add a logo/image by embedding it directly into the signature or hosting it externally and linking to it. The vast majority of email clients display l…

    733 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    23 Experts available now in Live!

    Get 1:1 Help Now