• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 1873
  • Last Modified:

I want to enable SHADOW COPIES on Windows 2008r2 and need advice

I would like to enable shadow copies on our main File Share. The file share is made up of two file servers that are part of a DFS. I am concerned about space and performance. Both my file servers have 1.39TB D drives that I share with DFS. Both servers have 460GB of free space at this time. All the DFS replication works fine, but if a user looses a file I need to go back to backups to restore a simple excel or word doc. I am hoping to offer shadow copies.  I see where I right click the D drive and "enable shadow copies". It looks like the default limits are about 10% of the actual drive size. I am assuming it is best to use limits. Is it possible for me to just enable this for say once a week to get thing started, so I can get the feel of how it works and watch what it does to my disk space? Do I just enable Shadow copies for the D drive and modify SETTINGS and check only one day of the week. What will this do to my drive space. Does it sound like I have sufficient space with only 460GB of 1.39TB available?
0
Thor2923
Asked:
Thor2923
2 Solutions
 
rscottvanCommented:
Everything you stated makes sense...

As far as having enough space, it really depends how much data changes how quickly.  Shadow Copies are pretty efficient, so I think you're likely fine.  (They only keep block level changes, so if only a few bytes in a file change, that's all it tracks.)

I would recommend setting it to run once daily, then see how much disk is free on day 2, then day 3.  I'm guessing your free space will only shrink by a couple percent per day.  That just means you would be able to hang on to about 5 to 10 days worth of changes.

Increasing the frequency of the snapshots doesn't necessarily increase the disk needed - it all depends how fast the files change.  In most of the cases I've done this, only a small fraction of the files change on any given day (less than 1%).  You will just have to experiment to tune it, but as long as its limited to 10% of the disk, there's little risk to you.  Any length of retention is better than you have now ;)
0
 
Henrik JohanssonSystems engineerCommented:
To avoid I/O burst issues, shadow copy snapshots should be placed on separate disk with 16KB cluster size NTFS. I've seen the shadow copy area be complete wiped earlier on our own file servers due to I/O burst when we had VSS area on same disk as the user data..

http://technet.microsoft.com/en-us/library/cc728305(v=ws.10).aspx
0

Featured Post

Creating Active Directory Users from a Text File

If your organization has a need to mass-create AD user accounts, watch this video to see how its done without the need for scripting or other unnecessary complexities.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now