Shadow Copies in 2008 R1 not using all allocated disk space

[zephyran]

We have a Windows 2008 R1 (with SP2) file server with three 3TB logical drives shared out. Two of the drives are in active use and thus have Shadow Copy set up on them. One in particular is configured to use 208 GB for Shadow Copies, and currently has 627 GB free. Last week it was using just under 60 GB for the Shadow Copies on that volume. The server was previously taking snapshots every 4 hours, but management requested it increased to every 2 hours.

I made that change on Friday, and this morning we've found that some older Shadow Copies from December were purged, and the server is now using 42 GB (much less than it was using before). I've searched for info on the Microsoft KB and Google, but seen no info on why the VSS would not use the maximum disk space configured for it, if that space was available.

Does anyone have any insight into this?

 

[BobbyCam]

Hi,

Im pretty sure shadow copies only keeps changed files, so it really depends on how often your files are changing as to the disk space it will us. What kinds of files are they and how often do they change?

Bobby