I have a customer that wants 2 luns presented to a windows 2008 filer server vm. He wants to use Windows File Server Resource Manager to control storage (dir's) for end users by taking advantage of the quota limits, and filtering file types available with FSRM. Basically he has limited room in aggr and volumes. Each vol will be 900GB with 5% snap reservea and fr 0%. From that 900GB luns only about 150-200GB will be unreserved (free). Now he wants snap shots for 1 week stored. I don't like the idea of this but he wants what he wants. My concern is space for overwrites for the luns. Should he disable snapshots unitl he can get more storage to the system to enable FR more + % and space reservation for the luns, and also use snap drive to try to free blocks when they are deleted from host. and use his MS FSRM to apply his quotas so storage won't grow?
It all depends on each LUNs growth rate. With 45TB of SnapShot reserve space as long as less than 45TB of data is not changed in the number of backup weeks retained they should be okay on space. The amount of free space seems quite small compared to the total size of the LUN though (900TB vs. 150-200GB)? In either case I would leave fractional reserve at 0%.
45TB SnapShot Reserve
150-200GB Free Space